Harmonic correction in power supplies feeding non-linear loads

This paper focuses on the design of an electronic circuit which can be used in conjunction with the power supplies used at the input of non-linear loads (computers, TV sets, etc.) in order to filter out the input current harmonics in such loads. The electronic circuit will fill the gaps of the distorted current waveform so that it becomes sinusoidal and also in phase with the mains supply. In this paper different configurations of the proposed electronic circuit are covered (depending on the location with respect to the non-linear load). An optimization algorithm is carried out in order to find the best location, minimum device rating for different type of loads. The proposed circuit monitors the input current, output voltage and power rating of the power supply. The circuit will then decide whether to filter the input current harmonics or the output voltage harmonics. The circuit will also optimize the best switching frequency for the required load so that the power supply operates at the maximum possible efficiency

The use of information systems for logistics and supply chain management in South East Europe: Current status and future direction

This research aims to investigate the current status and future direction of the use of information systems for logistics and supply chain management (LSCM) in South East Europe. The objectives are threefold: (1) to identify major challenges and developments on the use of information systems for LSCM by enterprises, (2) to examine the actual level of satisfaction of current policy on LSCM, and (3) to reveal the actual need of enterprises in South East Europe on effective use of information systems for LSCM. Mixed methodology of literature review and questionnaire survey is adopted in this research. Data collected from 79 enterprises are analysed using descriptive analysis in SPSS. The findings suggest that enterprises in Albania, Bulgaria, Greece, Former Yugoslav Republic of Macedonia (FYROM), Romania, and Serbia and Montenegro, face similar challenges but all are in different stages of developments of LSCM. Their use of information systems explains their heavy focus on supply chain partnership and weakness in demand chain partnership. Major findings suggest that companies and governments alike in that region do not seem to be ready for playing a significant and demanding role in global supply chains. Current deficiencies, including limited abilities in building valuable forward relations, weak strategic planning and organisation, and infrastructural problems, are major obstacles for fast development in LSCM. At the same time though, traces of changing mentalities do exist, setting the ground for improved performance and ultimately for a better position in global business

Hierarchy and Competition in CSCW applications: Model and case study

CSCW applications need to adapt themselves to the functional and organizational structures of people that use them. However they do not usually support division in groups with a certain hierarchical structure among them. In this paper, we propose and study a theoretical model of groupware appliations that reflects those hierarchical interactions. The proposed model is also intended to evaluate the effects in performance derived from competitive and collaborative relationships among the components of a hierarchy of groups. In order to demonstrate the above ideas, a groupware game, called Alymod, was designed and implemented using a modified version of a well-known CSCW Toolkit, namely Groupkit. Groupkit was modified in order to support group interactions in the same CSCW application. In Alymod, participants compete or collaborate within a hierarchical structure to achieve a common goal (completing gaps in a text, finishing numerical series, resolving University course examinations, etc.).Publicad

Applying Recommendations to Align Competences, Methodology, and Assessment in Telematics, Computing, and Electronic Engineering Courses

The alignment between competences, teachinglearning methodologies, and assessment is a key element of European higher education. This paper presents the efforts carried out by six telematics, computer science and electronic engineering education teachers toward achieving this alignment in their subjects. In a joint work with pedagogues, a set of recommended actions are identified. A selection of these actions are applied and evaluated in the six subjects. The cross analysis of the results indicates that the actions allow students to better understand the methodologies and assessments planned for the subjects, facilitate (self-) regulation, and increase students’ involvement in the subjects

Altered rich club and frequency-dependent subnetworks organization in mild traumatic brain injury: A MEG resting-state study

Functional brain connectivity networks exhibit “small-world” characteristics and some of these networks follow a “rich-club” organization, whereby a few nodes of high connectivity (hubs) tend to connect more densely among themselves than to nodes of lower connectivity. The Current study followed an “attack strategy” to compare the rich-club and small-world network organization models using Magnetoencephalographic (MEG) recordings from mild traumatic brain injury (mTBI) patients and neurologically healthy controls to identify the topology that describes the underlying intrinsic brain network organization. We hypothesized that the reduction in global efficiency caused by an attack targeting a model’s hubs would reveal the “true” underlying topological organization. Connectivity networks were estimated using mutual information as the basis for cross-frequency coupling. Our results revealed a prominent rich-club network organization for both groups. In particular, mTBI patients demonstrated hypersynchronization among rich-club hubs compared to controls in the d band and the d-g1, "-g1, and b-g2 frequency pairs. Moreover, rich-club hubs in mTBI patients were overrepresented in right frontal brain areas, from " to g1 frequencies, and underrepresented in left occipital regions in the d-b, d-g1, "-b, and b-g2 frequency pairs. These findings indicate that the rich-club organization of resting-state MEG, considering its role in information integration and its vulnerability to various disorders like mTBI, may have a significant predictive value in the development of reliable biomarkers to help the validation of the recovery frommTBI. Furthermore, the proposed approachmight be used as a validation tool to assess patient recovery

Una experiencia de formación colaborativa y práctica real entre la universidad y un centro educativo generando un espacio CSCL

Esta experiencia refleja la respuesta que le hemos dado en la necesidad de contextualizar los procesos de enseñanza en la formación de maestros y la fundamental coordinación de los trabajos que se realizan en la universidad para llevar a cabo nuestra labor. La unión de dos asignaturas troncales en el plan de estudios de magisterio (Didáctica General y Nuevas Tecnologías aplicadas a la Educación), junto con la participación de un Centro Escolar (C.P. Vicente Aleixandre de Valladolid), ha posibilitado la interconexión de contenidos teóricos de ambas asignaturas y la perspectiva práctica que aporta el Colegio. Todo ello tomando como eje un entorno colaborativo de trabajo en red, Basic Support for Cooperative Work (BSCW) que nos ha permitido generar una dinámica de formación CSCL (Computer Support for Colaborative Learnin). En este trabajo se incluye una descripción del proyecto con su intrincado cúmulo de relaciones e interconexiones, así como la valoración del primer año de trabajo.This experience shows the answer that we give to the need of relating theory and practice in maestriʹs formation. The union of two main subjects of study in the curriculum (Didáctica General y Nuevas Tecnologías aplicadas a la Educación) , along with the participation of an school (C.P. Vicente Aleixandre) , has made the interconnection of theoretic contentses of both subjects of study and the practical perspective that the School contributes . All of it taking like axle a collaborative surroundings of net work, Basic Support for Cooperative Work (BSCW), that has permitted us generating a dynamics of formation (Computer Supported Collaborative Learning). In this work a description of project with his intricate relational accumulation and interface are included, as well as the evaluation of first year of workEsta experiência reflete a resposta que nós temos dado à necessidade de contextualizar os processos de ensino na formação de professores e a fundamental coordenação dos trabalhos que realizam‐se na universidade para levar a cabo nosso labor. A união de duas disciplinas troncais no plano de estudos de Magistério (Didática Geral e Novas Tecnologías aplicadas à Educação) junto com a participação de um Centro Escolar (C. P. Vicente Aleixandre de Valladolid), tem possibilitado a interconexão dos conteúdos teóricos de ambas disciplinas e a perspectiva prática que aporta o Colégio. Tudo isto tomando como eixo um meio colaborativo de trabalho em rede, Basic Support for Cooperativ Work (BSCW) que permitiu‐nos gerar uma dinâmica de formação CSCL (Computer Support for Colaborative Learning). Neste trabalho se inclui uma descrição do projeto com seu enredado conjunto de relações e interconexões, bem como a valoração do primeiro ano de trabalho

Immunolocalisation of phosphorylated STAT3, interleukin 11 and leukaemia inhibitory factor in endometrium of women with unexplained infertility during the implantation window.

BACKGROUND: Uterine receptivity and embryo implantation are critical in the establishment of pregnancy. The diagnosis of endometrial fertility requires more precise measurements of endometrial receptivity. Interleukin (IL-11) and leukemia inhibitory factor (LIF) are essential for murine implantation and signal via intracellular phosphorylation (p) of STAT3 in the endometrium. Both cytokines are present in the endometrium of women duiring the receptive window. Endometrial IL-11, IL-11 receptor alpha (IL-11Ralpha), LIF and pSTAT3 in women with primary unexplained infertility was compared to normal fertile women during the implantation window. METHODS: LH timed endometrial biopsies (LH+6 to LH+10) were collected from women with unexplained infertility and normal fertility. pSTAT3, IL-11, IL-11Ralpha and LIF production was determined by immunohistochemistry. Staining intensity was determoned by two independent observers blind to the fertility status of the patient from whom the biopsy was taken. Staining intensity and heterogeneity in each of the endometrial compartments (epithelium; stroma, including decidualized stromal cells; and vasculature) was assessed. The Mann-Whitney U test was used to analyze IL-11, pSTAT3, IL-11Ralpha and LIF immunostaining intensities in the samples. RESULTS: IL-11, IL-11Ralpha and LIF were present predominantly in glandular epithelium, whilst luminal epithelium showed patchy staining. pSTAT3 was present in both glandular epithelium and stroma. IL-11 and pSTAT3 immunostaining was significantly lower in glandular epithelium in infertile women compared to controls (P < 0.05) whilst IL-11Ralpha and LIF staining did not differ. CONCLUSION: This is the first demonstration of reduced endometrial pSTAT3 and IL-11 in some women with unexplained infertility. This suggests IL-11 and pSTAT3 may be involved in the secretory transformation of glandular epithelium during receptivity. Reduced IL-11 production and STAT3 phosphorylation may contribute to unexplained infertility in some women.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

Using late-time optical and near-infrared spectra to constrain Type Ia supernova explosion properties

The late-time spectra of Type Ia supernovae (SNe Ia) are powerful probes of the underlying physics of their explosions. We investigate the late-time optical and near-infrared spectra of seven SNe Ia obtained at the VLT with XShooter at $>$200 d after explosion. At these epochs, the inner Fe-rich ejecta can be studied. We use a line-fitting analysis to determine the relative line fluxes, velocity shifts, and line widths of prominent features contributing to the spectra ([Fe II], [Ni II], and [Co III]). By focussing on [Fe II] and [Ni II] emission lines in the ~7000-7500 \AA\ region of the spectrum, we find that the ratio of stable [Ni II] to mainly radioactively-produced [Fe II] for most SNe Ia in the sample is consistent with Chandrasekhar-mass delayed-detonation explosion models, as well as sub-Chandrasekhar mass explosions that have metallicity values above solar. The mean measured Ni/Fe abundance of our sample is consistent with the solar value. The more highly ionised [Co III] emission lines are found to be more centrally located in the ejecta and have broader lines than the [Fe II] and [Ni II] features. Our analysis also strengthens previous results that SNe Ia with higher Si II velocities at maximum light preferentially display blueshifted [Fe II] 7155 \AA\ lines at late times. Our combined results lead us to speculate that the majority of normal SN Ia explosions produce ejecta distributions that deviate significantly from spherical symmetry.Comment: 17 pages, 12 figure, accepted for publication in MNRA

Urinary Paraben Concentrations and Ovarian Aging among Women from a Fertility Center

Background: Parabens are preservatives commonly used in personal care products, pharmaceuticals, and foods. There is documented widespread human exposure to parabens, and some experimental data suggest that they act as estrogenic endocrine disruptors. As far as we are aware, no epidemiologic studies have assessed female reproductive health effects in relation to paraben exposure. Objective: We examined the association of urinary paraben concentrations with markers of ovarian reserve in a prospective cohort study of women seeking fertility treatment at Massachusetts General Hospital, Boston, Massachusetts. Methods: Measures of ovarian reserve were day-3 follicle-stimulating hormone (FSH), antral follicle count (AFC), and ovarian volume. Paraben concentrations [methylparaben (MP), propylparaben (PP), and butylparaben (BP)] were measured in spot urine samples collected prior to the assessment of outcome measures. We used linear and Poisson regression models to estimate associations of urinary paraben concentrations (in tertiles) with ovarian reserve measures. Results: Of the women enrolled in 2004–2010, 192 had at least one ovarian reserve outcome measured (mean age ± SD, 36.1 ± 4.5 years; range, 21.0–46.7 years). MP and PP were detected in > 99% of urine samples and BP in > 75%. We found a suggestive trend of lower AFC with increasing urinary PP tertiles [mean percent change (95% CI) for tertiles 2 and 3 compared with tertile 1, respectively, were –5.0% (–23.7, 18.4) and –16.3% (–30.8, 1.3); trend p-value (ptrend) = 0.07] as well as higher day-3 FSH with higher urinary PP tertiles [mean change (95% CI) for tertiles 2 and 3 compared with tertile 1 were 1.16 IU/L (–0.26, 2.57) and 1.02 IU/L (–0.40, 2.43); ptrend = 0.16]. We found no consistent evidence of associations between urinary MP or BP and day-3 FSH or AFC, or between urinary MP, PP, or BP and ovarian volume. Conclusions: PP may be associated with diminished ovarian reserve. However, our results require confirmation in further studies. Citation: Smith KW, Souter I, Dimitriadis I, Ehrlich S, Williams PL, Calafat AM, Hauser R. 2013. Urinary paraben concentrations and ovarian aging among women from a fertility center. Environ Health Perspect 121:1299–1305; http://dx.doi.org/10.1289/ehp.120535

Laparoscopic adjustable gastric banding – should a second chance be given?

Background: Obesity is a chronic relapsing-remitting disease and a global pandemic, being associated with multiple comorbidities. Laparoscopic adjustable gastric banding (LAGB) is one of the safest surgical procedures used for the treatment of obesity, and even though its popularity has been decreasing over time, it still remains an option for a certain group of patients, producing considerable weight loss and improvement in obesity-associated comorbidities. Methods: The aim of this study was to evaluate the impact of weight loss following LAGB on obesity-associated comorbidities, and to identify factors that could predict better response to surgery, and patient sub-groups exhibiting greatest benefit. A total of 99 severely obese patients (81.2% women, mean age 44.19 ± 10.94 years, mean body mass index (BMI) 51.84 ± 8.77 kg/m2) underwent LAGB in a single institution. Results obtained 1, 2, and 5 years postoperatively were compared with the pre-operative values using SPPS software version 20. Results: A significant drop in BMI was recorded throughout the follow-up period, as well as in A1c and triglycerides, with greatest improvement seen 2 years after surgery (51.8 ± 8.7 kg/m2 vs 42.3 ± 9.2 kg/m2, p < 0.05, 55.5 ± 19.1 mmol/mol vs 45.8 ± 13.7 mmol/mol, p < 0.05, and 2.2 ± 1.7 mmol/l vs 1.5 ± 0.6 mmol/l). Better outcomes were seen in younger patients, with lower duration of diabetes before surgery, and lower pre-operative systolic blood pressure. Conclusions: Younger age, lower degree of obesity, and lower severity of comorbidities at the time of surgery can be important predictors of successful weight loss, making this group of patients the ideal candidates for LAGB