Improving distribution system state estimation with synthetic measurements

Distribution state estimation is a desired feature of modern power systems. The availability of measurements from smart meters has opened the door to extend the application of state estimation techniques down to end customers, preferably at the secondary distribution transformer level. However, the light coupling between phases makes the estimation of certain state variables, such as voltage phase angles, a great challenge. This paper proposes the use of synthetic measurements as a means of including cross-coupled information in the available set of measurements. This possibility can be easily implemented in line supervisors located at secondary transformer stations without the need for new hardware, just by embracing a different connection of measurement devices. This work demonstrates that this costless action results in a strong reduction of the sensibility of phase angle estimation errors with respect to measurement noise, thus leading to an important improvement in the quality of the results.publishedVersio

Clinical Symptoms in Fibromyalgia Are Better Associated to Lipid Peroxidation Levels in Blood Mononuclear Cells Rather than in Plasma

This is an open-access article distributed under the terms of the Creative Commons Attribution License.[Background] We examined lipid peroxidation (LPO) in blood mononuclear cells (BMCs) and plasma, as a marker of oxidative damage, and its association to clinical symptoms in Fibromyalgia (FM) patients. [Methods]: We conducted a case–control and correlational study comparing 65 patients and 45 healthy controls. Clinical parameters were evaluated using the Fibromyalgia Impact Questionnaire (FIQ), visual analogues scales (VAS), and the Beck Depression Inventory (BDI). Oxidative stress was determined by measuring LPO in BMCs and plasma. [Results]: We found increased LPO levels in BMCs and plasma from FM patients as compared to normal control (P<0.001). A significant correlation between LPO in BMCs and clinical parameters was observed (r = 0.584, P<0.001 for VAS; r = 0.823, P<0.001 for FIQ total score; and r = 0.875, P<0.01 for depression in the BDI). We also found a positive correlation between LPO in plasma and clinical symptoms (r = 0.452, P<0.001 for VAS; r = 0.578, P<0.001 for FIQ total score; and r = 0.579, P<0.001 for depression in the BDI). Partial correlation analysis controlling for age and BMI, and sex, showed that both LPO in cells and plasma were independently associated to clinical symptoms. However, LPO in cells, but not LPO in plasma, was independently associated to clinical symptoms when controlling for depression (BDI scores). [Discussion]: The results of this study suggest a role for oxidative stress in the pathophysiology of fibromyalgia and that LPO in BMCs rather than LPO in plasma is better associated to clinical symptoms in FM.This work was supported by Spanish FIS PI080500 grant, and FIS EC08/00076 grant, Ministerio de Sanidad, Spain, and Federación Andaluza de Fibromialgia y Fatiga Crónica (ALBA Andalucía). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewe

The MUSE view of the host galaxy of GRB 100316D

The low distance, $z=0.0591$, of GRB 100316D and its association with SN 2010bh represent two important motivations for studying this host galaxy and the GRB's immediate environment with the Integral-Field Spectrographs like VLT/MUSE. Its large field-of-view allows us to create 2D maps of gas metallicity, ionization level, and the star-formation rate distribution maps, as well as to investigate the presence of possible host companions. The host is a late-type dwarf irregular galaxy with multiple star-forming regions and an extended central region with signatures of on-going shock interactions. The GRB site is characterized by the lowest metallicity, the highest star-formation rate and the youngest ($\sim$ 20-30 Myr) stellar population in the galaxy, which suggest a GRB progenitor stellar population with masses up to 20 -- 40 $M_{\odot}$. We note that the GRB site has an offset of $\sim$660pc from the most luminous SF region in the host. The observed SF activity in this galaxy may have been triggered by a relatively recent gravitational encounter between the host and a small undetected ($L_{H\alpha} \leq 10^{36}$ erg/s) companion

Age-Related Immunity to Meningococcal Serogroup C Vaccination: An Increase in the Persistence of IgG2 Correlates with a Decrease in the Avidity of IgG

Contains fulltext : 97618.pdf (publisher's version ) (Open Access)Background All children and adolescents between 1 and 19 years of age in The Netherlands received a single meningococcal serogroup C conjugate (MenCC) vaccine in 2002. During follow-up 4–5 years later, the persistence of MenC polysaccharide-specific IgG was found to be dependent on age of vaccination with higher IgG levels in the oldest immunized age categories. Methods and Findings Two cross-sectional population-based serum banks, collected in 1995/1996 and in 2006/2007, were used for this study. We measured MenC polysaccharide-specific IgM, the IgG1 and IgG2 subclasses and determined the avidity of the IgG antibodies. We report that the age-related persistence of IgG after immunization with the MenCC vaccine seemed to result from an increase of IgG2 levels with age, while IgG1 levels remained stable throughout the different age-cohorts. Furthermore, an age-related increase in IgM levels was observed, correlating with the persistence of IgG antibodies with age. It is noteworthy that the increase in IgG2 correlated with a reduced IgG-avidity with age. Conclusion These date indicate that the classical characteristics of a T-cell-dependent antibody response as elicited by protein based vaccines might not be completely applicable when conjugate vaccines are administered to older children and adolescents up to 18 years of age. The response elicited by the MenCC vaccine seemed to be more a mixture of both T cell dependent and T cell independent responses in terms of humoral immunological characteristics

Exploring the impact of cumulative testing on academic performance of undergraduate students in Spain

The final publication is available at Springer via http://dx.doi.org/10.1007/s11092-014-9208-zFrequent testing provides opportunities for students to receive regular feedback and to increase their motivation. It also provides the instructor with valuable information on how course progresses, thus making it possible to solve the problems encountered before it is too late. Frequent tests with noncumulative contents have been widely analysed in the literature with inconclusive results. However, cumulative testing methods have hardly been reported in higher education courses. This paper analyses the effect of applying an assessment method based on frequent and cumulative tests on student performance. Our results show that, when applied to a microeconomics course, students who were assessed by a frequent, cumulative testing approach largely outperformed those assessed with a single final exam.Doménech I De Soria, J.; Blázquez Soriano, MD.; De La Poza, E.; Muñoz Miquel, A. (2015). Exploring the impact of cumulative testing on academic performance of undergraduate students in Spain. Educational Assessment, Evaluation and Accountability. 27(2):153-169. https://doi.org/10.1007/s11092-014-9208-zS153169272Adelman, HS, & Taylor, L. (1990). Intrinsic motivation and school misbehaviour some intervention implications. Journal of Learning Disabilities, 23, 541–550.Biggs, J, & Tang, C. (2007). Teaching for quality learning at university 3rd edn. Open University Press.Boston, C. (2002). The concept of formative assessment. Practical Assessment Research & Evaluation 8.Brown, GA, Bull, J, Pendlebury, M. (1997). Assessing Student Learning in Higher Education, 1st edn. Routledge.Cano, MD. (2011). Students’ involvement in continuous assessment methodologies: a case study for a distributed information systems course. IEEE Transactions on Education, 54, 442–451.Casem, ML (2006). Active learning is not enough. Journal of College Science Teaching, 35.Chen, J, & Lin, TF. (2008). Class attendance and exam performance a randomized experiment. The Journal of Economic Education, 39, 213–227.Chickering, AW, & Gamson, ZF. (1987). Seven principles for good practice in undergraduate education. American Association for Higher Education Bulletin, 39, 3–7.Crooks, TJ. (1988). The impact of classroom evaluation practices on students. Review of Educational Research, 58, 438–481.De Paola, M, & Scoppa, V. (2011). Frequency of examinations and student achievement in a randomized experiment. Economics of Education Review, 30, 1416–1429.Deck, W. (1998). The effects of frequency of testing on college students in a principles of marketing course, PhD thesis, Virginia Polytechnic Institute and State University. Virginia: Blacksburg.Dempster, FN. (1991). Synthesis of research on reviews and tests. Educational Leadership, 48, 71–76.Dochy, F. (2008). The Edumetric Quality of New Modes of Assessment: Some Issues and Prospects. Assessment, Learning and Judgement in Higher Education. Dordrecht: Springer Netherlands.Eikner, AE, & Montondon, L. (2001). Evidence on factors associated with success in intermediate accounting I. Accounting Educators’ Journal 13.Emerson, TLN, & Mencken, KD. (2011). Homework to require or not? online graded homework and student achievement Perspectives on Economic Education Research 7.Fulkerson, F, & Martin, G. (1981). Effects of exam frequency on student performance, evaluations of instructor, and test anxiety. Teaching of Psychology, 8, 90–93.Furnham, A, & Chamorro-Premuzic, T. (2005). Individual differences and beliefs concerning preference for university assessment methods. Journal of Applied Social Psychology, 35, 1968–1994.Gibbs, G, & Simpson, C. (2005). Conditions under which assessment supports students’ learning Learning and Teaching in Higher Education 1 (August 5, 2011)3–31.Haberyan, KA. (2003). Do weekly quizzes improve student performance on general biology exams?. The American Biology Teacher, 65, 110–114.Kling, N, McCorkle, D, Miller, C, Reardon, J. (2005). The impact of testing frequency on student performance in a marketing course. Journal of Education for Business, 81, 67–72.Kuh, GD (2003). What we’re learning about student engagement from NSSE Change 35.Kuo, T, & Simon, A. (2009). How many tests do we really need. College Teaching, 57, 156–160.Leeming, FC. (2002). The exam-a-day procedure improves performance in psychology classes. Teaching of Psychology, 29, 210–212.Lumsden, KG, Scott, A, Becker, WE. (1987). The economics student reexamined Male-female differences in comprehension. Journal of Economic Education, 18, 365–375.Marriott, P. (2009). Students’ evaluation of the use of online summative assessment on an undergraduate financial accounting module. British Journal of Educational Technology, 40, 237–254.Marriott, P, & Lau, A. (2008). The use of on-line summative assessment in an undergraduate financial accounting course. Journal of Accounting Education, 26, 73–90.McNabb, R, Pal, S, Sloane, P. (2002). Gender differences in educational attainment. the case of university students in england and wales. Economica, 69, 481–503.Miller, F. (1987). Test frequency, student performance and teacher evaluation in the basic marketing class. Journal of Marketing Education, 9, 14–19.Nicol, DJ, & Macfarlane Dick, D. (2006). Formative assessment and self-regulated learning, A model and seven principles of good feedback practice. Studies in Higher Education, 31, 199–218.Nowell, C, & Alston, RM. (2007). I thought I got an A! Overconfidence across the economics curriculum. The Journal of Economic Education, 38, 131–142.Race, P (1995). The art of assessing 1 New Academic 4.Scriven, M. (1967). The Methodology of Evaluation, vol 1 (pp. 39–83). Chicago: Rand McNally.Skinner, BF. (1974). About behaviorism. New York: Alfred A Knopf.Taras, M. (2005). Assessment - summative and formative - some theoretical reflections. British Journal of Educational Studies, 53, 466–478.Trotter, E. (2006). Student perceptions of continuous summative assessment. Assessment & Evaluation in Higher Education, 31, 505–521.Yorke, M. (2003). Formative assessment in higher education: Moves towards theory and the enhancement of pedagogic practice. Higher Education, 45, 477–501

Genome of the Avirulent Human-Infective Trypanosome—Trypanosoma rangeli

Background: Trypanosoma rangeli is a hemoflagellate protozoan parasite infecting humans and other wild and domestic mammals across Central and South America. It does not cause human disease, but it can be mistaken for the etiologic agent of Chagas disease, Trypanosoma cruzi. We have sequenced the T. rangeli genome to provide new tools for elucidating the distinct and intriguing biology of this species and the key pathways related to interaction with its arthropod and mammalian hosts.  Methodology/Principal Findings: The T. rangeli haploid genome is ,24 Mb in length, and is the smallest and least repetitive trypanosomatid genome sequenced thus far. This parasite genome has shorter subtelomeric sequences compared to those of T. cruzi and T. brucei; displays intraspecific karyotype variability and lacks minichromosomes. Of the predicted 7,613 protein coding sequences, functional annotations could be determined for 2,415, while 5,043 are hypothetical proteins, some with evidence of protein expression. 7,101 genes (93%) are shared with other trypanosomatids that infect humans. An ortholog of the dcl2 gene involved in the T. brucei RNAi pathway was found in T. rangeli, but the RNAi machinery is non-functional since the other genes in this pathway are pseudogenized. T. rangeli is highly susceptible to oxidative stress, a phenotype that may be explained by a smaller number of anti-oxidant defense enzymes and heatshock proteins.  Conclusions/Significance: Phylogenetic comparison of nuclear and mitochondrial genes indicates that T. rangeli and T. cruzi are equidistant from T. brucei. In addition to revealing new aspects of trypanosome co-evolution within the vertebrate and invertebrate hosts, comparative genomic analysis with pathogenic trypanosomatids provides valuable new information that can be further explored with the aim of developing better diagnostic tools and/or therapeutic targets

Mapping of mosquito breeding sites in malaria endemic areas in Pos Lenjang, Kuala Lipis, Pahang, Malaysia

<p>Abstract</p> <p>Background</p> <p>The application of the Geographic Information Systems (GIS) to the study of vector transmitted diseases considerably improves the management of the information obtained from the field survey and facilitates the study of the distribution patterns of the vector species.</p> <p>Methods</p> <p>As part of a study to assess remote sensing data as a tool for vector mapping, geographical features like rivers, small streams, forest, roads and residential area were digitized from the satellite images and overlaid with entomological data. Map of larval breeding habitats distribution and map of malaria transmission risk area were developed using a combination of field data, satellite image analysis and GIS technique. All digital data in the GIS were displayed in the WGS 1984 coordinate system. Six occasions of larval surveillance were also conducted to determine the species of mosquitoes, their characteristics and the abundance of habitats.</p> <p>Results</p> <p>Larval survey studies showed that anopheline and culicine larvae were collected and mapped from 79 and 67 breeding sites respectively. Breeding habitats were located at 100-400 m from human settlement. Map of villages with 400 m buffer zone visualizes that more than 80% of <it>Anopheles maculatus s.s</it>. immature habitats were found within the buffer zone.</p> <p>Conclusions</p> <p>This study amplifies the need for a broadening of the GIS approach which is emphasized with the aim of rejuvenating the dynamic aspect of entomological studies in Malaysia. In fact, the use of such basic GIS platforms promote a more rational basis for strategic planning and management in the control of endemic diseases at the national level.</p

Tracing the wider impacts of biomedical research: A literature search to develop a novel citation categorisation technique

There is an increasing need both to understand the translation of biomedical research into improved healthcare and to assess the range of wider impacts from health research such as improved health policies, health practices and healthcare. Conducting such assessments is complex and new methods are being sought. Our new approach involves several steps. First, we developed a qualitative citation analysis technique to apply to biomedical research in order to assess the contribution that individual papers made to further research. Second, using this method, we then proposed to trace the citations to the original research through a series of generations of citing papers. Third, we aimed eventually to assess the wider impacts of the various generations. This article describes our comprehensive literature search to inform the new technique. We searched various databases, specific bibliometrics journals and the bibliographies of key papers. After excluding irrelevant papers we reviewed those remaining for either general or specific details that could inform development of our new technique. Various characteristics of citations were identified that had been found to predict their importance to the citing paper including the citation’s location; number of citation occasions and whether the author(s) of the cited paper were named within the citing paper. We combined these objective characteristics with subjective approaches also identified from the literature search to develop a citation categorisation technique that would allow us to achieve the first of the steps above, i.e., being able routinely to assess the contribution that individual papers make to further research.Medical Research Council as part of the MRC-NIHR Methodology Research Programme, and Professor Martin Buxton

Oxidative Stress Correlates with Headache Symptoms in Fibromyalgia: Coenzyme Q10 Effect on Clinical Improvement

This is an open-access article distributed under the terms of the Creative Commons Attribution License.[Background]: Fibromyalgia (FM) is a chronic pain syndrome with unknown etiology and a wide spectrum of symptoms such as allodynia, debilitating fatigue, joint stiffness and migraine. Recent studies have shown some evidences demonstrating that oxidative stress is associated to clinical symptoms in FM of fibromyalgia. We examined oxidative stress and bioenergetic status in blood mononuclear cells (BMCs) and its association to headache symptoms in FM patients. The effects of oral coenzyme Q 10 (CoQ 10) supplementation on biochemical markers and clinical improvement were also evaluated. [Methods]: We studied 20 FM patients and 15 healthy controls. Clinical parameters were evaluated using the Fibromyalgia Impact Questionnaire (FIQ), visual analogues scales (VAS), and the Headache Impact Test (HIT-6). Oxidative stress was determined by measuring CoQ 10, catalase and lipid peroxidation (LPO) levels in BMCs. Bioenergetic status was assessed by measuring ATP levels in BMCs. [Results]: We found decreased CoQ 10, catalase and ATP levels in BMCs from FM patients as compared to normal control (P<0.05 and P<0.001, respectively) We also found increased level of LPO in BMCs from FM patients as compared to normal control (P<0.001). Significant negative correlations between CoQ 10 or catalase levels in BMCs and headache parameters were observed (r = -0.59, P<0.05; r = -0.68, P<0.05, respectively). Furthermore, LPO levels showed a significant positive correlation with HIT-6 (r = 0.33, P<.05). Oral CoQ 10 supplementation restored biochemical parameters and induced a significant improvement in clinical and headache symptoms (P<0.001). [Discussion]: The results of this study suggest a role for mitochondrial dysfunction and oxidative stress in the headache symptoms associated with FM. CoQ10 supplementation should be examined in a larger placebo controlled trial as a possible treatment in FM.This work has been supported by IV Plan Propio de Investigación (University of Seville, ref. 2010/00000453), FIS PI10/00543 grant, FIS EC08/00076 grant, Ministerio de Sanidad, Spain and Fondo Europeo de Desarrollo Regional (FEDER-Unión Europea), SAS 111242 grant, Servicio Andaluz de Salud-Junta de Andalucía, Proyecto de Investigación de Excelencia de la Junta de Andalucía CTS-5725 and Federación Andaluza de Fibromialgia y Fatiga Crónica (ALBA Andalucía).Peer Reviewe