bluuebunny/crossref_metadata_2025 huggingface dataset:
Pectin Extraction from Mango Peels in Batch Reactor: Dynamic One-Dimensional Modeling and Lattice Boltzmann Simulation
Authors: Durán Ricardo , Villa Aída L. , Ribeiro Rogers , Rabi José A.
Published: August 2015

A dynamic one-dimensional model accounting for pectin generation from protopectin in the solid matrix of mango peels and its degradation in both interstitial and extra-particle (i.e. reactor-filling) acid solution is proposed. The model assumes that pectin diffusive transport occurs in the interstitial fluid while eventual diffusive, thermal and pH influences in the solid phase were lumped into the kinetic coefficient of protopectin-pectin conversion. First-order kinetic was assumed to pectin degradation. Differential equations were numerically solved by adapting an in-house simulator of bioprocesses via the lattice Boltzmann method (LBM). As part of the LBM method, particle distribution functions were assigned to the pectin concentration in interstitial and reactor-filling fluid as well as assigned to the protopectin concentration in the solid phase. Equilibrium distribution functions were adopted by considering stationary solid phase, diffusive transport in interstitial fluid, and no spatial dependence in the reactor-filling fluid. Model parameters were assessed by comparing numerically simulated extraction yield curves with existing experimental data of pectin extraction using a batch reactor under either conventional or microwave heating. While the expected behavior of extraction yield curves was fairly reproduced in LBM simulations, discrepancies with respect to the experimental data can be assigned to assumptions in this preliminary model (e.g. first-order degradation kinetic and/or lumping effects into the protopectin-to-pectin kinetic). Prospective influence of slab thickness on extraction yields was also examined in LBM simulations.
A post-hoc Unweighted Analysis of Counter-Matched Case-Control Data
Authors: Rakovski Cyril , Langholz Bryan
Published: August 2015

Informative sampling based on counter-matching risk set subjects on exposure correlated with a variable of interest has been shown to be an efficient alternative to simple random sampling; however, the opposite is true when correlation between the two covariates is absent. Thus, the counter-matching design will entail substantial gains in statistical efficiency compared to simple random sampling at a first stage of analyses focused by design on variables correlated with the counter-matching variable but will lose efficiency at a second stage of analyses aimed at variables independent of the counter-matching variable and not conceived as a part of the initial study. In an effort to recover efficiency in such second stage of analyses scenarios, we considered a naive analysis of the effect of a dichotomous covariate on the disease rates in the population that ignores the underlying counter-matching sampling design. We derive analytical expressions for the bias and variance and show that when the counter-matching and the new dichotomous variable of interest are uncorrelated and a multiplicative main effects model holds, such an analysis is advantageous over the standard “weighted” approach, especially when the counter-matching variable is rare and in such scenarios the efficiency gains exceeds 80%. Moreover, we consider all possible conceptual violations of the required assumptions and show that moderate departures from the above-mentioned requirements lead to negligible levels of bias; numerical values for the bias under common scenarios are provided. The method is illustrated via an analysis of BRCA1/2 deleterious mutations in the radiation treatment counter-matched WECARE study of second breast cancer.
Fuzzy Logic Based Rotor Health Index of Induction Motor
Authors: Misra Rajul , Pahuja G. L.
Published: August 2015

This paper presents an experimental study on detection and diagnosis of broken rotor bars in Squirrel Cage Induction Motor (SQIM). The proposed scheme is based on Motor Current Signature Analysis (MCSA) which uses amplitude difference of supply frequency to upper and lower side bands. Initially traditional MCSA has been used for rotor fault detection. It provides rotor health index on full load conditions. However in real practice if a fault occurs motor can not run at full load. To overcome the issue of reduced load condition a Fuzzy Logic based MCSA has been designed, implemented, tested and compared with traditional MCSA. A simulation result shows that proposed scheme is not only capable of detecting the severity of rotor fault but also provides remarkable performance at reduced load conditions.
On-line Adaptive and Intelligent Distance Relaying Scheme for Power Network
Authors: Dubey Rahul , Samantaray S. R. , Panigrahi B. K. , Venkoparao G. V.
Published: August 2015

The paper presents an on-line sequential extreme learning machine (OS-ELM) based fast and accurate adaptive distance relaying scheme (ADRS) for transmission line protection. The proposed method develops an adaptive relay characteristics suitable to the changes in the physical conditions of the power systems. This can efficiently update the trained model on-line by partial training on the new data to reduce the model updating time whenever a new special case occurs. The effectiveness of the proposed method is validated on simulation platform for test system with two terminal parallel transmission lines with complex mutual coupling. The test results, considering wide variations in operating conditions of the faulted power network, indicate that the proposed adaptive relay setting provides significant improvement in the relay performance.
Unexpected documentation and inter-Andean range expansion of a vulnerable large mammal (Mammalia, Pilosa, Myrmecophaga tridactyla) in Colombia
Authors: Figel Joe J. , Botero-Cañola Sebastián , Sánchez-Londoño Juan David , Quintero-Ángel Andrés
Published: August 2015

The distribution of the giant anteater (
Application of ultrasonic-assisted injection molding for improving melt flowing and floating fibers
Authors: Yang Yi-Jen , Huang Chung-Ching , Tao Jie
Published: August 2015

In this study, we investigated the use of ultrasonic technology in assisted injection molding and mold designs. We used an ultrasonic device installed in a mold to vibrate a melt directly, thereby converting kinetic energy into thermal energy. In addition, we developed three flat specimens of different thicknesses (3, 1, and 3-1-3 mm) produced by ultrasonic-assisted injection molds. An ultrasonic oscillation device 45 mm in diameter was placed in the cavity and used to vibrate a polycarbonate or a polycarbonate with 30% glass fiber melt at a frequency of 20 kHz. Furthermore, cavity pressure sensors were positioned at the front and rear of the vibration region for analyzing the melt flow behavior under ultrasonic-assisted injection molding conditions. Because of the absorption of ultrasonic energy, local heat was generated inside the resin, thus forming an oscillatory flow during the packing and holding stages, improving the flow characteristics of the melt, and changing the melt flow behavior around the skin layer to reduce the molecular orientation and high shear effect. The freezing rate of the melt was also reduced to eliminate the glass fiber streaks, floating fibers, and fiber orientation, particularly for thinner parts; the hesitation phenomena were then improved to increase the weld line strength.
Production of no-carrier-added 135La at an 18 MeV cyclotron and its purification for investigations at a concentration range down to 10−15 mol/L
Authors: Mansel Alexander , Franke Karsten
Published: August 2015

The production of non-commercially available 135La by proton irradiation of an isotopically enriched [135Ba]BaCO3 target at a cyclotron is described. The purification of the radionuclide was performed by a La-selective resin. 135La was separated in no-carrier-added (n.c.a) form in a nitric acid solution with a radiochemical yield of 83 ± 5% and a total activity per batch of 43 ± 3 MBq. The enriched [135Ba]Ba was recycled to the carbonate form with a recovery of 90 ± 3%. On the basis of a detection limit of 1 Bq/mL, solutions of n.c.a. 135La could be measured down to the 10
–15 mol/L concentration range.
Neoadjuvant chemotherapy in 13 patients with locally advanced poorly differentiated thyroid carcinoma based on Turin proposal - a single institution experience
Authors: Besic Nikola , Dremelj Marta , Schwartzbartl-Pevec Andreja , Gazic Barbara
Published: August 2015

Background. There is a paradigm that chemotherapy is ineffective in thyroid carcinoma. The aim of our study was to find out whether neoadjuvant chemotherapy before thyroid surgery had an effect on the size of primary tumour in patients with poorly differentiated thyroid carcinoma (PDTC) based on Turin proposal.

Patients and methods. Altogether, 13 patients (8 women, 5 men; median age 61 years) with PDTC based on Turin proposal were treated with neoadjuvant chemotherapy between 1986 and 2005. Tumour diameter was from 4.5 to 18 cm (median 9 cm). Regional and distant metastases were detected in 6 and 9 patients, respectively. Eight patients had pT4 tumour.

Results. Altogether, 29 (range 1–5) cycles of chemotherapy were given. Tumour diameter decreased in all the patients and by more than 30% in 5 patients (= 38%). Two of these five patients had also preoperative external beam irradiation (EBRT). Total thyroidectomy, lobectomy and neck dissection were performed in 10, 3 and 5 cases, respectively. R0 and R1 resection was done in 5 and 8 cases, respectively. Eight patients had postoperative EBRT of the neck and upper mediastinum. The 5-year and 10-year cause-specific survival rates of patients were 66% and 20%, respectively.

Conclusions. After neoadjuvant chemotherapy a partial tumour regression was observed in 38% of patients with PDTC based on Turin proposal.
Impact of tumour volume on prediction of progression-free survival in sinonasal cancer
Authors: Hennersdorf Florian , Mauz Paul-Stefan , Adam Patrick , Welz Stefan , Sievert Anne , Ernemann Ulrike , Bisdas Sotirios
Published: August 2015

Background. The present study aimed to analyse potential prognostic factors, with emphasis on tumour volume, in determining progression free survival (PFS) for malignancies of the nasal cavity and the paranasal sinuses.

Patients and methods. Retrospective analysis of 106 patients with primary sinonasal malignancies treated and followed-up between March 2006 and October 2012. Possible predictive parameters for PFS were entered into univariate and multivariate Cox regression analysis. Kaplan-Meier curve analysis included age, sex, baseline tumour volume (based on MR imaging), histology type, TNM stage and prognostic groups according to the American Joint Committee on Cancer (AJCC) classification. Receiver operating characteristic (ROC) curve analysis concerning the predictive value of tumour volume for recurrence was also conducted.

Results. The main histological subgroup consisted of epithelial tumours (77%). The majority of the patients (68%) showed advanced tumour burden (AJCC stage III-IV). Lymph node involvement was present in 18 cases. The mean tumour volume was 26.6 ± 21.2 cm3. The median PFS for all patients was 24.9 months (range: 2.5–84.5 months). The ROC curve analysis for the tumour volume showed 58.1% sensitivity and 75.4% specificity for predicting recurrence. Tumour volume, AJCC staging, T- and N-stage were significant predictors in the univariate analysis. Positive lymph node status and tumour volume remained significant and independent predictors in the multivariate analysis.

Conclusions. Radiological tumour volume proofed to be a statistically reliable predictor of PFS. In the multivariate analysis, T-, N- and overall AJCC staging did not show significant prognostic value.
Gamma-enolase: a well-known tumour marker, with a less-known role in cancer
Authors: Vizin Tjasa , Kos Janko
Published: August 2015

Background. Gamma-enolase, known also as neuron-specific enolase (NSE), is an enzyme of the glycolytic pathway, which is expressed predominantly in neurons and cells of the neuroendocrine system. As a tumour marker it is used in diagnosis and prognosis of cancer; however, the mechanisms enrolling it in malignant progression remain elusive. As a cytoplasmic enzyme gamma-enolase is involved in increased aerobic glycolysis, the main source of energy in cancer cells, supporting cell proliferation. However, different cellular localisation at pathophysiological conditions, proposes other cellular engagements.

Conclusions. The C-terminal part of the molecule, which is not related to glycolytic pathway, was shown to promote survival of neuronal cells by regulating neuronal growth factor receptor dependent signalling pathways, resulting also in extensive actin cytoskeleton remodelling. This additional function could be important also in cancer cells either to protect cells from stressful conditions and therapeutic agents or to promote tumour cell migration and invasion. Gamma-enolase might therefore have a multifunctional role in cancer progression: it supports increased tumour cell metabolic demands, protects tumour cells from stressful conditions and promotes their invasion and migration.
Drug delivery and innovative pharmaceutical development in mimicking the red blood cell membrane
Authors: Naeem Sumaira , Kiew Lik Voon , Yong Chung Lip , Yin Yin Teo , Misran Misni Bin
Published: August 2015

Circulation half-life has become one of the major design considerations in nanoparticle drug delivery systems. By taking cues for designing long circulating carriers from natural entities such as red blood cells (RBCs) has been explored for many years. Among all the cellular carriers including leukocytes, fibroblasts, islets, and hepatocytes, RBCs offer several distinctive features. The present review underlines a discussion on the applications of different RBC carriers (RBC mimics) which can evade the body’s reticuloendothelial system overcoming many barriers such as size, shape, accelerated blood clearance, mechanical properties, control over particle characteristics, and surface chemistry. Bilayer membrane liposomes infusing phospholipids have long been synthesized to mimic bioconcave RBC carriers using the notion of stealth liposomes. This is not a comprehensive review; some illustrative examples are given on how they are currently obtained. A special attention is devoted to the RBC mimics from polymers, red cell membrane ghosts, and the red cell membrane enclosing polymeric cores as potential drug carriers. The present research reveals the achievement of RBC surface charge to accord with the immune system as a game of hide and seek in a much promising way in the light of its pharmaceutical applications.
Cooperativas de Crédito Brasileiras Adotam Monitoramento Internacional de Desempenho?
Authors: Oliveira Paulo Henrique Magalhães , Bressan Valéria Gama Fully
Published: August 2015

Purpose: The study examined if the Brazilian credit unions use the 'PEARLS' performance monitoring methodology proposed by the World Council of Credit Unions, and the perception of the analysts of the cooperative system on the relevance of the indicators of this system.Methods: We used qualitative research with a sample selected through accessibility. Data were obtained from structured interviews conducted with five analysts of Brazil's Central Bank and two managers of central credit cooperatives, in addition to response, via questionnaire, of seventeen managers of credit unions located in the northern, northeast, south and southeast regions of Brazil.Results: Most of the individual cooperatives and the two central credit unions analyzed were unaware of the PEARLS methodology. This monitoring system is known only by the analysts of the Central Bank of Brazil, indicating that only the supervisory agent of cooperatives in Brazil knows the internationally proposed system and the adapted version proposed to Brazilian reality.Limitations: The survey via questionnaires obtained only 1,4% of population response rate, and the results can not be generalized.Practical implications: It can be said that there is room for improving performance monitoring techniques, as the PEARLS is used in 97 countries and unknown both by individual cooperatives and credit central cooperatives surveyed in this study.Originality: It is noteworthy that studies of this problem applied to the Brazilian reality were not found to date.
Há Efeito Manada em Ações com Alta Liquidez do Mercado Brasileiro?
Authors: Silva Juliana Xavier Serapio da , Barbedo Claudio Henrique , Araújo Gustavo Silva
Published: August 2015

Purpose: This work aims to verify the herd behavior in both liquid stocks of Brazilian stock exchange, i.e. Petrobras and Vale.Methodology: This work uses the methods of Christie and Huang (1995) and price pressure with high frequency data to detect the herd behavior between 2010 and 2014.Findings: The first method suggest that there are no signs of herd behavior using 30 minutes intervals data. However, there is evidence of price pressure for the sample with all intraday data.Originality: Herd behavior studies usually focus on mutual funds. This work analyses the herd behavior based on individual stock prices.
Strategic Financial Performance Evaluation of the Iranian automotive industry Using Imperialist competitive Algorithm
Authors: Kaviani Meysam , Yazdani Maziyar
Published: August 2015

Purpose. This paper evaluates strategic financial performance of 10 Iranian stock exchange listed automotive companies over the period 2005-2009 at the hand of value-creating performance indicators and the Free Cash Flow derived value indicators.Design. To this effect, profiting from the Imperialist Competitive Algorithm (ICA), the understudy companies were assigned to three clusters in terms of debt structure, firm size, and growth opportunitiesFindings. The results, in general, indicate a significant correlation between value-based indicators Economic Value Added (EVA) and True Value Added (TVA) and the FCF-derived indicators Created Value from Free Cash Flow to Firm (CVFCFF) and Created Value from Free Cash Flow to Equity (CVFCFE), and between Market Value Added (MVA) and CVFCFF (one of the two FCF-derived indicators), while, according to the results, there is no significant correlation between the value-driven performance indicators Refined Economic Value Added (REVA) and Equity Economic Value Added (EEVA) and either of the FCF-derived indicators CVFCFF and CVFCFE.Originality. Present Paper, by company clustering in ICA environment, the companies are clustered based on their close similarity in all three criteria and subsequently for examination of each strategic performance indicator were subjected to correlation and Fisher (F) tests.
Stakeholders in Equity-Based Crowdfunding: Respective Risks Over the Equity Crowdfunding Lifecycle
Authors: Son Turan Semen
Published: August 2015

Objective. The purpose of this paper is to present a thorough research on the risk categories and specific risk factors that each immediate stakeholder faces over the equity crowdfunding lifecycle.Methodology. This study employs an exploratory approach, supported by current data to understand the global equity crowdfunding setting and the stakes for major players.Findings. Findings show that, although equity crowdfunding, can be a unique opportunity especially for underdeveloped countries and SMEs who have difficulty obtaining funding elsewhere, is also a potential peril for those who ignore or underestimate the overall and stand-alone risks that come along with each stage of the process. The findings have implications for all ventures seeking alternative financing venues, investors and equity crowdsourcing platforms. Furthermore, they pinpoint potential areas of further investigation for researchers and policy makers.Originality/Value. This study differentiates itself from the limited number of papers on equity crowdfunding, as a newly developing field of academic research, in that it underscores financial, regulatory, operational, reputational and strategic risks from several perspectives and offers recommendations on how these risks can be addressed.
The many ways to make a luminal cell and a prostate cancer cell
Authors: Strand Douglas W , Goldstein Andrew S
Published: August 2015

Research in the area of stem/progenitor cells has led to the identification of multiple stem-like cell populations implicated in prostate homeostasis and cancer initiation. Given that there are multiple cells that can regenerate prostatic tissue and give rise to prostate cancer, our focus should shift to defining the signaling mechanisms that drive differentiation and progenitor self-renewal. In this article, we will review the literature, present the evidence and raise important unanswered questions that will help guide the field forward in dissecting critical mechanisms regulating stem-cell differentiation and tumor initiation.
A new appraisal of iodine refractory thyroid cancer
Authors: Vaisman Fernanda , Carvalho Denise P , Vaisman Mario
Published: August 2015

Thyroid cancer incidence is increasing all over the world – mostly due to an increase in the detection of small tumors that were previously undetected. A small percentage of these tumors lose the ability to uptake and/or to respond to radioiodine (RAI) therapy, especially in metastatic patients. There are several new therapeutic options that have emerged in the last 5 years to treat RAI refractory thyroid cancer patients, however, it is very important to properly identify RAI refractory patients and to clarify those appropriate for these treatments. In this review, we discuss the RAI refractory definitions and the criteria that have been suggested based on RAI uptake in the post therapy scan, as well as the response after RAI therapy and the possible molecular mechanisms involved in this process. We offer a review of the therapeutic options available at the moment and the therapeutic considerations based on a patient's individualized personal characteristics, primary tumor histology, tumor burden and location and velocity of lesion growth.
Water quality modeling of the Medellin river in the Aburrá Valley
Authors: Giraldo Buitrago Lina Claudia , Palacio Carlos Alberto , Molina Rubén Darío , Agudelo García Rubén Alberto
Published: August 2015

Water quality modeling intends to represent a water body in order to assess their status and project the effects of different measures taken for their protection. This paper presents the results obtained from the Qual2kw model implementation in the first 50 kilometers of the Aburrá-Medellín River, in their most critical conditions of water quality, which correspond to low flow rates. After the model calibration, three recovery scenarios (short-term, medium-term and long-term) were evaluated. In the first scenario the sanitation only improved in some streams, in accordance with the Plan of Sanitation and Management of Discharges that was considered. Medium and long-term scenarios, with the operation of the new Water Waste Treatment Plant (WWTP) of the Bello municipality and an increase in the sewage collection, were considered. The obtained results show the positive impact of the operation of the WWTP of Bello in the balance of BOD5, dissolved oxygen and nitrogen.
Factors involved in the perceived risk of construction workers
Authors: Rodríguez-Garzón Ignacio , Martínez-Fiestas Myriam , Delgado-Padial Antonio , Lucas-Ruiz Valeriano
Published: August 2015

This article is an exploratory study of perceived risk in the construction sector. We used a sample of 514 workers in Spain, Peru and Nicaragua. The method used was the psychometric paradigm and, under its assumptions we have studied nine factors or qualitative attributes of risk. The main statistical analysis was carried out using a classification tree. As a result is obtained that four of the nine attributes studied predict significantly the perceived risk of the sample. The attribute on the delay of the consequences has been the most important predictor in the model, followed by the attribute that explores the potential catastrophic risk and the attribute that explores the serious consequences. Finally the attribute related to the personal vulnerability has emerged. The implications of the results are exposed.
Settlement analysis of friction piles in consolidating soft soils
Authors: Rodríguez Rebolledo Juan Félix , Auvinet-Guichard Gabriel Y. , Martínez-Carvajal Hernán E.
Published: August 2015

The paper shows how axisymmetric finite element numerical models can be used to optimize the design of friction piles foundations in an environment that is prone to regional subsidence. The study considers friction piles in typical Mexico City soft clays, that are subjected to external loads and soil consolidation due to variations in piezometric conditions. The constitutive models used to numerically simulate the behavior of the clays vary from a basic elastic perfectly-plastic model to a critical state model that is able to account for the anisotropic yielding behavior of Mexico City clay. The simulations consider the long term behavior of the internal piles within a large pile group.
How to promote distributed resource supply in a Colombian microgrid with economic mechanism?: System dynamics approach
Authors: Arango-Manrique Adriana , Carvajal-Quintero Sandra Ximena , Younes-Velosa Camilo
Published: August 2015

Distributed generation currently has caused an increase in the installation or renewable energy generation resources near the consumption centers and the ability to operate in the event of a failure of the interconnected system in isolation mode. However, this type of generation and operation has not progressed significantly in Colombia due to the lack of financial mechanisms. This paper presents a model in System Dynamics that proposed a mechanism for the promotion of distributed resources by including regulatory incentives known as Renewable Energy Premium Tariff and incentives for providing technical support for the distribution and transmission system. Proposed mechanisms help to promote the use of renewable energy in Colombia and further enhance the tools so that grid operators can avoid accidental disconnection.
Analysis of voltage sag compensation in distribution systems using a multilevel DSTATCOM in ATP/EMTP
Authors: Rojas-Cubides Herbert Enrique , Cruz-Bernal Audrey Soley , Rojas-Cubides Harvey David
Published: August 2015

Voltage sags are the most common power quality disturbances in electrical facilities. It may cause malfunction in sensitive equipment and process interruption. The distribution static compensator (DSTATCOM) is a device that can compensate voltage sags by injecting reactive power into distribution system. This paper shows the influence on voltage sags characteristics by the presence of twelve-pulse DSTATCOM in the modified IEEE-13 distribution system. The analysis is performed by means of a random generation of disturbances using a MATLAB routine to identify the critical buses of the test system. Further, the DSTATCOM model taking advantage of the available elements from ATP/EMTP software is described. Simulations show that when DSTATCOM is placed directly to affected bus it is possible to obtain a complete mitigation of the voltage sag. Finally, the relation between the reactive power injected by DSTATCOM, the type of voltage sag and the location of affected bus is considered.
Estimating the produced power by photovoltaic installations in shaded environments
Authors: Ramos-Paja Carlos Andrés , Saavedra-Montes Andrés Julián , Trejos Luz Adriana
Published: August 2015

A model to improve the estimation of the power and energy from photovoltaic installations under dynamic shading conditions is proposed in this paper. The model considers the shaded profile in each photovoltaic module and the temperature profile to update the model parameters of each photovoltaic module. The impact of dynamic shades on the power production is analyzed, illustrating the large errors introduced by classical prediction approaches, which consider non-shading at all or average shading.  Moreover, a procedure to model the shades profile in any environment is described and illustrated. Finally, experimental irradiance and environment temperature profiles are used to evaluate the performance of the proposed model in contrast with the classical approaches. The results illustrate that the classical approaches overestimate the power produced by the photovoltaic array, in contrast with the power produced by the proposed model.
Voltage Regulation in a Power Inverter Using a Quasi-Sliding Control Technique
Authors: Toro-García Nicolás , Garcés-Gómez Yeison Alberto , Hoyos-Velasco Fredy Edimer
Published: August 2015

This paper shows the behavior of a three-phase power converter with resistive load using a quasi-sliding and a chaos control techniques for output voltage regulation. Controller is designed using Zero Average Dynamic (ZAD) and Fixed Point Inducting Control (FPIC) techniques. Designs have been tested in a Rapid Control Prototyping (RCP) system based on Digital Signal Processing (DSP) for dSPACE platform. Bifurcation diagrams show the robustness of the system. Chaos detection is a signal processing method in the time domain, and has power quality phenomena detection applications. Results show that the phase voltage in the load has sinusoidal performance when it is controlled with these techniques. When delay effects are considered, experimental and numerical results match in both of stable and transition to chaos zones.
Representation of Electric Power Systems by Complex Networks with Applications to Risk Vulnerability Assessment
Authors: Correa-Henao Gabriel Jaime , Yusta-Loyo José María
Published: August 2015

The occurrence of impact events (e.g. blackouts with vast geographic coverage) into electrical critic infrastructure systems usually require the analysis of cascade failure root causes through the conduction of structural vulnerability studies, with well-defined methodologies that may guide decision-making for implementation of preventing actions and for operation recovering into the power system (e.g. N-1 and N-t contingency studies). This technical contribution provides some alternative techniques based upon complex networks and graph theory, which in the last few years have been proposed as useful methodologies for analysis of physical behavior of electric power systems. Vulnerability assessment is achieved by testing their performance into random risks and deliberate attacks threats scenarios. Results shown in this proposal lead to conclusions on the use of complex networks for contingency analysis by means of studies of those events that result in cascade failures and consumer disconnections.
Vulnerability Assessment of Power Systems to Intentional Attacks using a Specialized Genetic Algorithm
Authors: Agudelo Laura , López-Lezama Jesús María , Muñoz Galeano Nicolás
Published: August 2015

A specialized genetic algorithm applied to the solution of the electric grid interdiction problem is presented in this paper. This problem consists in the interaction of a disruptive agent who aims at maximizing damage of the power system (measured as load shed), and the system operator, who implements corrective actions to minimize system load shed. This problem, also known as “the terrorist threat problem”, is formulated in a bilevel programming structure and solved by means of a genetic algorithm. The solution identifies the most vulnerable links of the network in terms of a terrorist attack, providing signals for future reinforcement of the network or more strict surveillance of critical elements. The proposed approach has been tested on three case studies: a didactic five-bus power system, a prototype of the Colombian power system and the IEEE Reliability Test System. Results show the robustness and applicability of the proposed approach.
Epidemiological approach to assess risk factors and current distortion incidence on distribution networks
Authors: Romero Miguel Fernando , Gallego Luis Eduardo , Pavas Fabio Andrés
Published: August 2015

A methodology based on epidemiological analysis for assessing risk factors and harmonic distortion incidence rate in a distribution network is proposed in this paper. The methodology analyzes the current harmonics emission risk at the PCC due to the connection of disturbing loads. These loads are modeled and multiple loads connection scenarios are simulated using Monte Carlo Algorithms. From the simulation results, potential risk factors for critical harmonics indicators are identified, leading to a classification of the scenarios into groups of exposed or unexposed to risk factors. Finally, the incidence rate of harmonics is calculated for each load connection scenario and the risk of critical harmonics scenarios due to the exposure to risk factors is estimated.
Generalities about Design and Operation of Microgrids
Authors: Rey-López Juan Manuel , Vergara-Barrios Pedro Pablo , Osma-Pinto Germán Alfonso , Ordóñez-Plata Gabriel
Published: August 2015

The need of new generation systems have motivated the development of microgrids. This new concept may bring significant benefits to the transmission and distribution networks as losses reduction, high degree of efficiency and reliability. This paper presents generalities about microgrids, including general structure and different topologies; also it is proposed an original methodology for facilitating its design and evaluation. Finally, it's analyzed the microgrid located at the Parque Tecnológíco de Guatiguará at the Universidad Industrial de Santander, included an operation analysis for different operations stages of loads and generation,  the performance of operation of storage systems, the interaction with the grid and an energy balance for all the system.
Modeling Dynamic Procurement Auctions of Standardized Supply Contracts in Electricity Markets including Bidders Adaptation
Authors: Torres-Valderrama Henry Camilo , Gallego-Vega Luis Eduardo
Published: August 2015

Descendant Clock Auctions have been increasingly used in power markets. Traditional approaches are focused on discovering the bidders’ best response but neglecting the bidders’ adaptation. This paper presents an algorithm based on decision theory to estimate the bidders’ behavior along the auction. The proposed model uses portfolio concepts and historical data of spot market to estimate a long term contract supply curve. This model was applied to evaluate the Colombia’s Organized Market (MOR). Demand curve parameters and round size were varied to evaluate their impact over auction outputs. Results show that demand curve has a quite small impact over bidders’ decisions and round size management is useful to avoid non-competitive bidders’ behavior. In addition, it is shown that auction’s starting prices strongly influence auction’s clearing prices. These results are extremely helpful to design market structures in power markets.
La práctica de la evaluación del riesgo de violencia en España
Authors: Singh Jay P , Arbach-Lucioni Karin , Desmarais Sarah L. , Hurducas Cristina , Condemarin Carolina , Dean Kimberlie , Doyle Michael , Folino Jorge O. , Godoy-Cervera Verónica , Grann Martin , Y. Ho Robyn M. , Large Matthew M. , Pham Thierry H. , Hjort Nielsen Louise , Rebocho Maria Francisca , Reeves Kim A. , Rettenberger Martin , De Ruiter Corine , Seewald Katharina
Published: August 2015

La valoración del riesgo de violencia es un requisito fundamental en la toma de decisiones profesionales que implican prevenir, intervenir o informar sobre la conducta de las personas. El uso de herramientas estructuradas mejora la precisión de las evaluaciones basadas en el juicio clínico en contextos psiquiátricos, penitenciarios y jurídicos. Este estudio presenta resultados de la primera encuesta sobre el uso de herramientas de evaluación del riesgo de violencia y sobre su utilidad percibida en España. Las escalas de psicopatía (PCL-R y PCL:SV) y el HCR-20 encabezaron la lista de las herramientas más usadas tanto por elección personal como por requisito institucional. Se ofrecen datos novedosos sobre las prácticas profesionales de evaluación del riesgo de violencia que pueden orientar a los profesionales que desempeñan su tarea en contextos sanitarios, correccionales y forenses, donde los instrumentos estructurados son frecuentemente usados para asistirlos en la toma de
decisiones.
Alimentación penitenciaria: entre higiene y derechos
Authors: Bejarano Roncancio Jhon Jairo
Published: August 2015

Resumen

La Comisión Interamericana de Derechos Humanos (CIDH) y el Comité Internacional de la Cruz Roja (CICR) recomiendan las condiciones en las cuales debe desarrollarse la detención de las personas privadas de la libertad, incluyendo las referidas al suministro de alimentación, permitiendo que sobre esa base se constituyan las normas, procesos y procedimientos en los Establecimientos de Reclusión del Orden Nacional (ERON). En Colombia, y en muchos otros países, estos escenarios de producción de alimentación resultan insuficientes; entre las variables a considerar se encuentran la infraestructura física, el tipo de contratación, los hábitos alimentarios regionales por la procedencia heterogénea de la población interna y muchas veces sus preferencias, las patologías crónicas que se manejan, la seguridad en el ingreso de materias primas y el suministro de la alimentación al interior de los ERON. Es importante mencionar que cualquier brote de enfermedad trasmitida por alimentos (ETA) puede desencadenar una epidemia que se complica aún más por la situación de reclusión. Otras dificultades son la comercialización no permitida, el ingreso de alimentos y la conservación de estos en las celdas, lo cual puede ocasionar la pérdida de calidad higiénico-sanitaria y pone en peligro la salud de esta población.

 

Palabras clave: Alimentación colectiva; Derechos humanos; Prisiones; Enfermedades transmitidas por alimentos (DeCS).

 

Summary

The Inter-American Commission on Human Rights (IACHR) and the International Committee of the Red Cross (ICRC) recommend the conditions under which the detention of persons deprived of liberty must be developed, including those relating to food supply. This establishes the basis for the standards, processes and procedures in National Order Detention Facilities (ERON, in its Spanish acronym). In Colombia, and in many other countries, these scenarios of food production are insufficient; among the variables to consider are the physical infrastructure, contract types, regional food habits due to the heterogeneous origin of the inmate population and often their preferences, chronic pathologies that are handled, the security for raw materials entrance and food supply within the ERON. It is noteworthy that any outbreak of foodborne disease (FBD) can trigger an epidemic that is further complicated by the situation in prison. Other difficulties are non-permitted marketing, food entrance and its conservation in the cells, which can produce loss of sanitary quality and endanger the health of this population.

 

Keywords: Collective feeding; Human rights; Prisons; Foodborne diseases (MeSH).
Análisis del concepto ‘justicia’ en terapia ocupacional
Authors: Parra Eliana
Published: August 2015

Antecedentes: El campo de estudio de la Terapia Ocupacional ha venido ampliándose debido a la necesidad de dar respuesta a las demandas de las personas y comunidades. En este sentido es preciso profundizar sobre el tema de justicia en la profesión.

Objetivo: Analizar el concepto justicia en Terapia Ocupacional en el periodo comprendido entre los años 2000 y 2014 a través de los distintos textos encontrados.

Métodos: El estudio es de tipo descriptivo en el cual se realizó una revisión de literatura y análisis de la misma teniendo en cuenta los conceptos encontrados en los textos y su aporte teórico y práctico para la Terapia Ocupacional.

Resultados: El concepto de justicia se ha incorporado al campo de estudio de la Terapia Ocupacional, encontrando las categorías justicia social y justicia ocupacional.

Conclusión: Se recomienda continuar construyendo conceptualmente la justicia ocupacional a partir de la reflexión en la profesión y la experiencia dada por la aplicación de estos conceptos en Terapia Ocupacional.
Intoxicación letal con Aldicarb: Análisis de sangre postmortem mediante LC-ESI-MS/MS
Authors: Mariño Gaviria Diana Jazmín , Patiño Reyes Nancy
Published: August 2015

El Aldicarb es un plaguicida carbamato de alta toxicidad asociado a intoxicaciones agudas fatales en Colombia.  El presente estudio describe un método analítico para la determinación cuantitativa de aldicarb en sangre postmortem.  Básicamente el método consiste en una precipitación de proteínas de la sangre para luego ser analizada por LC-ESI-MS/MS utilizando el aldicarb-d3 como estándar interno. El método desarrollado en este trabajo fue aplicado a siete casos de intoxicación letal presuntamente con este plaguicida. El aldicarb se encontró en sangre en niveles desde 0,10 y 2,5 µg/mL. De los resultados obtenidos no sólo se expone la utilidad de emplear LC-ESI-MS/MS en el análisis de aldicarb en sangre para su aplicación en toxicología forense con el propósito de contribuir a la búsqueda de la causa de muerte, sino que además evidencia el empleo de este plaguicida en actos suicidas.   
SALUD MENTAL EN TIEMPOS DE GUERRA: Una Reflexión sobre la Relación Conflicto Armado – Salud Mental en el Pueblo Indígena Emberá en Situación de Desplazamiento Forzado, Bogotá 2012 – 2014
Authors: Ruiz Eslava Luisa Fernanda
Published: August 2015

Resumen

 

Antecedentes: El proyecto de investigación, busco realizar un acercamiento a la relación conflicto armado – salud mental, tomando como marco de comprensión el punto de vista del pueblo Emberá, la medicina social latinoamericana, el sujeto como protagonista de la vida relacional – colectiva, y la salud mental positiva.

Objetivo: Comprender la naturaleza de la relación conflicto armado – salud mental en el pueblo indígena Emberá en situación de desplazamiento forzado en la ciudad de Bogotá.

Materiales y Métodos: La investigación se desarrolló desde un método cualitativo empleando técnicas mixtas, basado en una fundamentación epistemológica desde el pensamiento complejo y la hermenéutica interpretativa.

Resultados: Comprender el conflicto armado como un mecanismo que fuerza a la población indígena Emberá a desplazarse a escenarios desconocidos y violentos los cuales afectan en conjunto el Sentirse Bien y el Buen Vivir, además de sus condiciones y calidad de vida.

Conclusiones: Entre las consecuencias más atroces de la guerra se encuentra la pérdida, la transformación y desestructuración de la cultura indígena Emberá. Por esta razón, es necesario implementar estrategias que permitan fortalecer la identidad cultural, la educación tradicional, las redes de apoyo, los factores solidarios y la memoria colectiva.

 
Association of Depression and Stress in Acute Myocardial Infarction: a case-control study
Authors: Goldfeld Patricia RM , Soares Luciana S. , Manfroi Waldomiro C.
Published: August 2015

Background: Psychosocial factors have been reported to be independently associated with coronary artery disease (CAD). However, the stress variable is still sub detailed and there are few studies that used coronary angiography (CA) to assess CAD.

Objectives: To compare levels of depression, stress and stressful life events in three groups of individuals: post-MI (Myocardial Infarction) patients; patients presenting symptoms and no previous MI, who underwent cardiac catheterization and had non-significant obstructive CAD and individuals with no symptoms of cardiac disease or others diseases.

Methods: We conducted a case-control study, with two cases groups and one control group. The study included 105 patients with recent Myocardial Infarction (MI group), 101 patients with cardiac symptoms and normal CA (CS group), and 100 patients without symptoms of disease (NS group). Multivariate logistic regression was used to assess, stress and vital events, with an Odds Ratio of 95% confidence interval (CI), controlling for age, sex, education level, income, social support group, Body Mass Index (BMI), sedentary lifestyle and family history of MI or sudden death.

Results: MI patients group showed depression with an OR= 4.47(95% CI, 2:36 to 8:46, p<.001), and stress OR= 5.37(95%CI, 2.94-9.78, p <.001) whereas CS group showed depression: OR= 6.95(95%CI, 3.64-13.28, p <.001) and stress: OR = 9.18 (95%CI, 4.73-17.82, p <.001) compared to patients without symptoms. After adjusting for risk factors: age, sex, education, income, social support, obesity, sedentary lifestyle, family history of MI or sudden death, the OR showed the following variation: in the MI group, depression OR= 2.51 (95%CI, 1:05 to 5:98, p = .038), stress, OR= 8.76(95%CI, 3:48 to 22:01, p <.001), and CS group, depression OR= 3.25(95%CI, 1.40-7.55,p <01) and stress OR= 12.24 (95%,      CI, 4.81-31.14, p <.001). The raised effect of variable stress after adjustment was promoted by the age, sex and physical inactivity variables, and did not affect the significance level (p <.001).

Conclusions: This study has demonstrated that subjects with cardiac symptoms without overt CAD, present similar depression and/or stress levels than post-MI patients. And also, post-MI patients and CS patients have more stress and depression than controls, even when adjusted for age, sex, education level, family income, social support, obesity, sedentary lifestyle and family history of MI and / or sudden death.
VIOLENCIA EN EL TRABAJO EN EL SECTOR PÚBLICO DE LA SALUD: UNA VISIÓN DESDE LAS PERSONAS TRABAJADORAS. BOGOTÁ, COLOMBIA 2011 – 2012
Authors: Luna–García Jairo Ernesto , Urrego Mendoza Zulma , Gutiérrez Robayo Mireya , Martínez Durán Alejandro
Published: August 2015

Objetivo: Identificar situaciones de violencia directa, estructural y cultural percibidas en sus ámbitos laborales por personas trabajadoras de los hospitales públicos y la Secretaría Distrital de Salud de Bogotá, como parte de un estudio marco sobre condiciones psicosociales de trabajo en el sector público de la salud.
Métodos: Abordaje cualitativo, comprendiendo 6 grupos focales organizados según perfil laboral así: Líderes trabajadores; Trabajadores de Salud Pública; Trabajadores de diferentes áreas; Trabajadores del área directiva; Trabajadores del área asistencial; y Trabajadores del área administrativa; análisis narrativo de las correspondientes transcripciones.
Resultados: La violencia estructural en el sector público de la salud ha incrementado desde la reforma al sistema de salud y sus impactos en términos de flexibilización laboral; conllevando incremento en la violencia directa, al verse involucradas las personas trabajadoras de salud en la negación del derecho a la salud y en procesos de competencia e individualización de la atención; respecto a la violencia cultural, la discriminación aparece como el elemento más relevante, repercutiendo en relaciones interpersonales negativas y en violación de derechos.
Conclusiones: las reformas neoliberales al sistema de salud colombiano han generado una problemática crítica en torno a las prácticas de la salud organizadas desde el sector público y a las condiciones de contratación del personal que allí labora. Se requiere un cambio en la orientación del sistema de salud, así como la garantía de condiciones de empleo digno y decente, junto con acciones para prevenir la violencia directa hacia las personas trabajadoras de las instituciones públicas de salud en Bogotá.
Investigación en salud para la paz de Colombia: ¿estudiar la noviolencia o la violencia?
Authors: Urrego Mendoza Zulma Consuelo , Escobar Córdoba Franklin
Published: August 2015

Los acuerdos de paz de La Habana se encuentran en curso desde hace varios meses, y han generado  gran expectativa en la población colombiana. En este escenario, resulta importante reflexionar cuál ha de ser el foco de construcción de conocimiento desde nuestras profesiones que pueda contribuir de la mejor forma para lograr un escenario futuro en el que podamos vivir en paz, con dignidad y justicia social, y en el que se impida la reactivación de nuevos ciclos de violencia masiva por la vía de haberse superado sus determinantes profundos.