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El trabajo pretende medir los niveles de eficiencia técnica de la minería zacatecana durante el periodo de intensificación de la actividad que corresponde a la primera década del siglo XXI, utilizando el análisis de envoltura de datos. La medición obtenida permite señalar que en términos generales el sector es ineficiente a nivel de los estados más representativos. Además, que las clases tradicionalmente especializadas se ubican en la frontera de la eficiencia tomando en cuenta la estructura productiva al interior del estado, situación que obedece a su posición como referentes a nivel nacional en el ámbito de dichas actividades. Se sugiere con ello un punto de partida para revisar el desempeño relativo del sector minero en la actualidad con el propósito de contar con más elementos para establecer políticas que favorezcan una mayor y mejor integración con los mercados.

Modern power systems face several problems at frequencies above the range of traditional stability studies due to the increasing penetration of power electronic devices. This phenomenon has been recently referred to as electromagnetic transient stability and is a common issue in systems with power electronic converters at any power and voltage level, such as FACTS, HVDC, power electronic interfaces for grid connection of renewable energies, custom power devices for power quality enhancement, among others. The study of power systems stability is usually carried out by simulation tools that represent the power system through phasor models. However, due to the faster dynamics of modern systems, the harmonic interaction among the controllers, the converters, and the electric power components, recent research results suggest that some stability analysis should be conducted with models suitable for wider frequency ranges, e.g., electromagnetic transient models. This paper reviews the use of frequency domain methods to analyze the influence of the modeling approach of passive power components on the results of electromagnetic transient stability studies. ispartof: IEEE TRANSACTIONS ON POWER DELIVERY vol:35 issue:1 pages:71-83 status: Published online

The COVID-19 pandemic has been the most critical public health issue in modern his-tory due to its highly infectious and deathly potential; and the limited access to massive, low-cost, and reliable testing has significantly worsened the crisis. The recovery and the vaccination of millions of people against COVID-19, have made serological tests highly relevant to identify the presence and levels of SARS-CoV-2 antibodies. Due to its advantages, microfluidic-based technologies represent an attractive alternative to the conventional testing methodologies used for these purposes. In this work, we describe the development of an automated ELISA on-chip capable of detecting anti-SARS-CoV-2 antibodies in serum samples from COVID-19 patients and vaccinated individuals. The colorimetric reactions were analyzed with a microplate reader. No statistically significant differences were observed when comparing the results of our automated ELISA on-chip against the ones obtained from a traditional ELISA on a microplate. Moreover, we demonstrated that it is possible to carry out the analysis of the colorimetric reaction by performing basic image analysis of photos taken with a smartphone, which constitutes a useful alternative when lacking specialized equipment or a laboratory setting. Our automated ELISA on-chip has the potential to be used in a clinical setting and mitigate some of the burden caused by testing deficiencies.

Credential theft is a serious driver of cybercrime today. The world over, different kinds of credentials are used by billions daily to authenticate themselves in their physical and digital lives. From physical keys, to tokens and cards, to digital private keys, session cookies, digital certificates, crypto-currency wallets, login and password combinations, all of these types of credentials are vulnerable to attack. Credential theft is a serious driver of cybercrime today. The world over, different kinds of credentials are used by billions daily to authenticate themselves in their physical and digital lives. From physical keys, through tokens and cards, to digital private keys, session cookies, digital certificates, crypto-currency wallets, login and password combinations, all of these types of credentials are vulnerable to attack. But what happens after they are compromised? Jose Miguel Esparza of Blueliv follows the lifespan of stolen credentials, from theft to being exploited for profit.

Background Opioid-induced constipation (OIC) is a frequent and bothersome adverse event related with opioid therapy in cancer patients. Despite the high prevalence, medical management of OIC is often uncertain. The current project aimed to investigate expert opinion on OIC management and provide practical recommendations to improve the clinical approach of OIC in cancer patient. Methods A modified Delphi method was conducted involving 46 different physicians experts in OIC. Using a structured questionnaire of 67 items this project intended to seek consensus on aspects related to diagnosis, treatment, and quality of life of cancer patients suffering with OIC. Results After two rounds, a consensus was reached in 91% of the items proposed, all in agreement. Agreement was obtained on OIC definition (95.7%). Objective and patient-reported outcomes included in that definition should be assessed routinely in clinical practice. Responsive to symptom changes and easy-to-use assessment tools were recommended (87.2%). Successful diagnosis of OIC requires increase clinicians awareness of OIC and proactivity to discuss symptoms with their patients (100%). Successful management of OIC requires individualization of the treatment (100%), regular revaluation once is established, and keeping it for the duration of opioid treatment (91.5%). Oral Peripherally Acting μ-Opioid Receptor Agonists (PAMORAs), were considered good alternatives for the treatment of OIC in cancer patients (97.9%). This drugs and laxatives can be co-prescribed if OIC coexist with functional constipation. Conclusions The panelists, based on their expert clinical practice, presented a set of recommendations for the management of OIC in cancer patients.

espanolRESUMEN El dolor lumbar (LBP, por sus siglas en ingles) es un problema comun e importante, con una elevada prevalencia en mujeres y ancianos. Es una causa importante de dolor, discapacidad y detrimento economico. En la mayoria de los casos, el dolor se alivia en cuatro a seis semanas y las personas pueden regresar a sus actividades normales. La acupuntura para el tratamiento del dolor lumbar inespecifico sigue siendo un tema bajo investigacion. Hemos realizado en este trabajo una revision de los articulos mas importantes publicados en los ultimos 7 anos (2013-2019), verificando el crecimiento en los ultimos anos de las terapias alternativas. La acupuntura ha demostrado superioridad en la mejoria del dolor lumbar inespecifico cuando se ha comparado con la opcion de ningun tratamiento y, fundamentalmente, cuando se asocia a tratamiento convencional como complemento del mismo. EnglishABSTRACT Low back pain (LBP) is a common and important problem, with a high prevalence in women and the elderly. It is an important cause of pain, disability and economic detriment. In most cases, the pain is relieved in four to six weeks and people can return to normal activities. Acupuncture for the treatment of nonspecific low back pain remains a topic under investigation. We have carried out in this work a review of the most important articles published in the last 7 years (2013-2019), verifying the growth in the last years of alternative therapies. Acupuncture has demonstrated superiority in the improvement of non-specific low back pain when compared to the option of no treatment and, fundamentally, when it is associated with conventional treatment as a complement to it.

The objective of this paper is to develop household susceptibility indices related to disruptions in infrastructure services during disasters. The prolonged disruptions in infrastructure services create great hardship for the households of a community affected by natural hazards, especially shelter-in-place households who are at a high risk of such disruptions. The literature currently lacks tools and methods to assist decision makers in considering the tolerance and susceptibility of the household in communities to the infrastructure service disruptions. While there are some vulnerability indices in the disaster literature, the scores have not developed to specifically consider the risks associated with the infrastructure service disruptions. Hence, in this study, we developed and implemented Disruption Tolerance Index (DTI) to enable understanding of spatial patterns of susceptibility to service disruptions. In particular, we create susceptibility scores and maps for disruptions in power and transportation systems as two essential services on which households rely during their daily life. These service disruptions include power outages and road closures due to the natural hazards which disrupted households' access to these services. The factors for determining DTI scores are selected through an empirical analysis of households’ susceptibility to the disruptions, the scores are calculated by implementing Principal Components Analysis, and the scale of the scores is discussed. The study reveals the hot spots and cold spots of compound susceptibility to the disruptions. Unveiling the spatial clusters of susceptibility provides decision makers with the necessary information to consider the households' susceptibility in emergency plans and risk mitigation practices. The approach developed in this study could be adapted for different locations to enable understanding of the unique susceptibility of the households from the infrastructure services during disasters. Such understanding provides the decision-makers with the essential information to plan and mitigate the risk mitigation approaches and preparedness actions related to the risks associated with infrastructure service disruptions.

The undesirable harmonic distortion produced by distributed generation units (DGUs) based on power-electronic inverters presents operating and power-quality challenges in electric systems. The level of distortion depends on the internal elements of the DGUs as well as on the characteristics of the grid, loads, and controls, among others. This paper presents a comprehensive method, focused on power-quality indexes and efficiency for the design of microgrids with multiple DGUs interconnected to the ac grid through three-phase multi-Megawatt medium-voltage pulsewidth-modulated-voltage-source inverters (PWM-VSI). The proposed design method is based on a least square solution using the harmonic domain modeling approach to effectively consider explicitly the harmonic characteristics of the DGUs and their direct and cross-coupling interaction with the grid, loads, and the other DGUs. Extensive simulations and analyses against PSCAD are presented in order to show the outstanding performance of the proposed design approach.

Circulating tumor cells (CTCs) have the potential of becoming the gold standard marker for cancer diagnosis, prognosis and monitoring. However, current methods for its isolation and characterization suffer from equipment variability and human operator error that hinder its widespread use. Here we report the design and construction of a fully automated high-throughput fluorescence microscope that enables the imaging and classification of cancer cells that were labeled by immunostaining procedures. An excellent agreement between our machine vision-based approach and a state-of-the-art microscopy equipment was achieved. Our integral approach provides a path for operator-free and robust analysis of cancer cells as a standard clinical practice.

Background It has been estimated that 20% of the general population will suffer shoulder pain throughout their lives, with a prevalence that can reach up to 50%. The suprascapular nerve (SSN) provides sensation for the posterior and superior regions of the glenohumeral joint, whereas the anterior and inferior zones and the skin are innervated mostly by the axillary nerve. Pulsed radiofrequency on the SSN has been proposed as a therapeutic option in chronic shoulder pain. Axillary nerve block has been proposed in the context of surgical analgesia as an adjuvant to SSN block. Interventions Ultrasound (US)-guided techniques target the nerve selectively, minimizing patients’ and physicians’ exposure to harmful radiation while increasing success rates by better needle placement. We perform both US-guided techniques with the patient in a lateral decubitus position with the affected shoulder on the upper side. Objective The aim of this report is to describe the adaptation of a US-guided technique that targets both the suprascapular and axillary nerves for the treatment of painful shoulder syndrome. The simultaneous pulsed radiofrequency on the suprascapular and axillary nerves for the treatment of the chronic condition of shoulder pain has been scarcely studied, with very few references in the literature. Conclusions By adapting an approach developed in acute pain management, we can safely deliver pulsed radiofrequency to the suprascapular and axillary nerves for the treatment of shoulder pain.

Background and objectivesIn the context of opioid-sparing perioperative management, there is still little evidence from randomized controlled trials regarding the effectiveness of interfascial thoracic blocks. This study hypothesizes that receiving a serratus plane block reduces opioid requirements, pain scores, and rescue medication needs.MethodsThis double-blind, randomized controlled study was conducted on 60 adult females undergoing oncologic breast surgery. After general anesthesia, patients were randomly allocated to either conventional analgesia (control group, n=30) or single-injection serratus block with L-bupivacaine 0.25% 30mL (study group, n=30). First 24-hour total morphine consumption (primary outcome), pain scores at 1, 3, 6, 12, and 24 hours, time-to-first opioid rescue analgesia, and adverse effects were recorded.ResultsMedian 24 hours’ opioid dose was greater in the control group (median difference 9 mg (95% CI 4 to 14.5 mg); pConclusionsInterfascial serratus plane block reduces opioid requirements and is associated with better pain scores and lower and later rescue analgesia needs in the first 24 hours, compared with conventional intravenous analgesia, in breast surgery.Trial registration numberNCT02905149.

BACKGROUND: Tracheal intubation failure in patients with difficult airway is still not uncommon. While videolaryngoscopes such as the Glidescope offer better glottic vision due to an acute-angled blade, this advantage does not always lead to an increased success rate because successful insertion of the tube through the vocal cords may be the limiting factor. We hypothesize that combined use of Glidescope and fiberscope used only as a dynamic guide facilitates tracheal intubation compared to a conventional Glidescope technique with a preshaped nondynamic stylet. METHODS: One hundred sixty adult patients with predicted difficult airway were randomly assigned to a conventional Glidescope (standard Glidescope group) or a combined Glidescope + fiberscope group intubation. In the Glidescope + fiberscope group under direct vision from the Glidescope, tracheal intubation was performed using the fiberscope as a guide without using fiberoptic vision, while in the standard Glidescope group, a conventional stylet-guided intubation technique was performed. We evaluated the rate of tracheal intubation success at first attempt as the primary end point (Fisher exact test). The difference between groups in airway injury, time to successful intubation, and the need for an alternative technique was also evaluated. RESULTS: First-attempt intubation success was higher in the Glidescope + fiberscope group than in the standard Glidescope group (91% vs 67%; P = .0012; fragility index, 8; absolute risk reduction, 24% [95% CI, 12%-36%]). Median time to successful tracheal intubation was shorter in the Glidescope + fiberscope group (50 vs 64 seconds; P = .035). Airway injury rate was lower in the Glidescope + fiberscope group than in the standard Glidescope group (1% vs 11%; P = .035; fragility index, 1; absolute risk reduction, 10% [95% CI, 3%-18%]). Alternative rescue technique requirements to achieve tracheal intubation were higher in the standard Glidescope group (24% vs 4%; P < .001; fragility index, 7). CONCLUSIONS: The use of a dynamic, flexible guide during a Glidescope laryngoscopy in patients with a predicted difficult airway compared to a standard intubation technique improves first-attempt intubation success, decreases the incidence of airway injury and time to successful intubation, as well as the need of an alternative technique to succeed.

The detection and analysis of circulating tumor cells (CTCs) may enable a broad range of cancer-related applications, including the identification of acquired drug resistance during treatments. However, the non-scalable fabrication, prolonged sample processing times, and the lack of automation, associated with most of the technologies developed to isolate these rare cells, have impeded their transition into the clinical practice. This work describes a novel membrane-based microfiltration device comprised of a fully automated sample processing unit and a machine-vision-enabled imaging system that allows the efficient isolation and rapid analysis of CTCs from blood. The device performance was characterized using four prostate cancer cell lines, including PC-3, VCaP, DU-145, and LNCaP, obtaining high assay reproducibility and capture efficiencies greater than 93% after processing 7.5 mL blood samples from healthy donors, spiked with 100 cancer cells. Cancer cells remained viable after filtration due to the minimal shear stress exerted over cells during the procedure, while the identification of cancer cells by immunostaining was not affected by the number of non-specific events captured on the membrane. We were also able to identify the androgen receptor (AR) point mutation T878A from 7.5 mL blood samples spiked with 50 LNCaP cells using RT-PCR and Sanger sequencing. Finally, CTCs were detected in 8 of 8 samples from patients diagnosed with metastatic prostate cancer (mean $\pm$ SEM = 21 $\pm$ 2.957 CTCs/mL, median = 21 CTC/mL), thereby validating the potential clinical utility of the device., Comment: 13 pages, 6 figures, under review

Most of the passive component design approaches for VSC-based devices do not explicitly consider its nonlinear and discontinuous interaction with the power network. In addition, only an operating point is considered in those designs approaches, but in practical applications, the performance over an operating region has to be ensured due to operative changes in the grid. These situations lead to conservative filter designs with oversized passive elements that require iterations between the design and the simulation/implementation stages to meet the imposed power quality restrictions, with no guarantee of proper performance if the grid parameters are changed. This paper presents the calculation of steady state modulation parameters (CSSMPs) and the exact design (ED) approaches to perform steady state analysis and component design in grid connected VSC-based systems. The proposed formulation is based on the extended harmonic domain (EHD) and explicitly considers the switching process and their constant steady state modulation parameters. Although the proposed approach is applicable for any passive filters configuration, an L-filter active rectifier is used as the test system. The design results are the passive components values and modulating parameters required to meet the design restrictions, explicitly considering the modulation technique used. Time domain simulations validate this design proposal in all the presented cases. The performed analysis gives very useful information about feasible operating region, the number of control solutions, the operating limits of the system under load and voltage source variations, and the effect of the modulation technique.

The objective of this study is to examine and quantify the relationships among sociodemographic factors, damage claims, and social media attention on areas during natural disasters. Social media has become an important communication channel for people to share and seek situational information to learn of risks, to cope with community disruptions, and to support disaster response. Recent studies in disaster informatics have recognized the presence of bias in the representation of social media activity in areas affected by disasters. To explore related factors for such bias, existing studies have used geo-tagged tweets to assess the extent of social media activity in disaster-affected areas to evaluate whether vulnerable populations remain silent on social media. However, less than 1% of all tweets are actually geo-tagged; therefore, attempts to understand the representativeness of geotagged tweets to the general population have shown that certain populations are over- or underrepresented. To address this limitation, this study examined the attention given to locations based on social media content. The study conducted a content-based analysis to filter tweets related to 84 super-neighborhoods in Houston during Hurricane Harvey and 57 cities in North Carolina during Hurricane Florence. By examining the relationships among sociodemographic factors, the number of damage claims, and the volume of tweets, the results showed that social media attention concentrates in populous areas, independent of education, language, unemployment, and median income. The relationship between population and social media attention is characterized by a sub-linear power law, indicating a large variation among the sparsely populated areas. Using a machine-learning model to label the topics of the tweets, the results showed that social media users pay more attention to rescue- and donation-related information; nevertheless, the topic variation is consistent across areas with different levels of attention. These findings contribute to a better understanding of the spatial concentration of social media attention regarding posting and spreading situational information in disasters. The findings could inform emergency managers and public officials to effectively use social media data for equitable resource allocation and action prioritization.

This paper presents a design method based on the extended harmonic domain modeling for L and LCL passive filters of active-front-end PWM two-level voltage source converters for grid-connected renewable energy sources. The proposed design method is tested under several operating scenarios, such as high and low power levels and switching frequencies. Also, a dedicated graphical user interface (GUI) with five other design methods is provided to ease the evaluation of the proposed design method. The GUI also computes the power quality indexes and the steady-state waveforms for each design methodology. In addition to this, an in-depth overview of filtering technologies and applications is presented to identify the primary practical use of passive filtering and to justify the use of LCL filter in grid-connected systems. The obtained results show that the proposed design method leads to the smallest passive filter parameters, and it is the only method that fulfills all the imposed power quality requirements as well as power specifications.

Averaged modeling is a commonly used approach used to obtain mathematical representations of VSC-based systems. However, essential characteristics mainly related to the modulation process and the harmonic distortion of the signals are not able to be accurately captured and analyzed. The extended harmonic domain (EHD) has recently been seen as an alternative modeling framework since it allows us to consider the harmonic interaction explicitly. However, there is not a clearly established methodology to derive the EHD models in the presence of power electronic switches. This paper presents a generalized methodology based on the switching instants to obtain large-signal EHD models of VSC-based power systems. Three model order reduction approaches are also proposed to address the increased size of the resulting EHD models. Analytic formulas of three modulation techniques: sinusoidal pulse-width modulation, third harmonic injection pulse-width modulation, and space vector pulse-width modulation are provided to obtain the open-loop large signal EHD models. A performance assessment of the proposed modeling approach in respect to model size, the computational time and the accuracy is presented based on simulations and experimental case studies. The obtained results show that the resulting EHD models are accurate and reliable, while the memory and computation time are improved with the proposed model order reductions.

We present the results of a pilot project of the Spanish Ministry of Health, Social Services and Equality, envisaged to the development of a national integrated data repository of maternal-child care information. Based on health information standards and data quality assessment procedures, the developed repository is aimed to a reliable data reuse for (1) population research and (2) the monitoring of healthcare best practices. Data standardization was provided by means of two main ISO 13606 archetypes (composed of 43 sub-archetypes), the first dedicated to the delivery and birth information and the second about the infant feeding information from delivery up to two years. Data quality was assessed by means of a dedicated procedure on seven dimensions including completeness, consistency, uniqueness, multi-source variability, temporal variability, correctness and predictive value. A set of 127 best practice indicators was defined according to international recommendations and mapped to the archetypes, allowing their calculus using XQuery programs. As a result, a standardized and data quality assessed integrated data respository was generated, including 7857 records from two Spanish hospitals: Hospital Virgen del Castillo, Yecla, and Hospital 12 de Octubre, Madrid. This pilot project establishes the basis for a reliable maternal-child care data reuse and standardized monitoring of best practices based on the developed information and data quality standards.

espanolLa radiofrecuencia pulsada (RFp) se ha utilizado para el tratamiento de nervios perifericos y del ganglio de la raiz dorsal (GRD). Comunmente se ha aplicado para tratamiento de dolor lumbar, cervical y neuropatias con muy buenos resultados. El ganglio de la raiz dorsal es una estructura anatomica que se encuentra situada bilateralmente en el extremo distal de la raiz dorsal en el espacio epidural lateral. La mayor parte de los GRD toracicos se localizan en la parte craneal medial de los agujeros intervertebrales. Los pacientes con dolor toracico irradiado siguiendo un patron segmentario, que no responden al tratamiento conservador, son susceptibles de tratamiento mediante RFp del GRD. Con el objetivo de salvar las dificultades tecnicas en el acceso al GRD toracico y de minimizar las posibles complicaciones yatrogenicas derivadas de la tecnica percutanea tradicional, decidimos realizar la tecnica de RFp en GRD a nivel toracico con cateter epidural mediante abordaje del espacio epidural via translaminar en dos pacientes afectos de radiculopatia toracica. El tratamiento del ganglio de la raiz dorsal a nivel lumbar es una terapia muy extendida en pacientes con dolor cronico lumbar radicular. Diversos estudios y revisiones avalan la realizacion de esta tecnica. Sin embargo, el dolor radicular toracico no es un sindrome clinico tipico como en el area lumbar. Existen diferentes patrones dolorosos: dolor constante o intermitente, dolor nociceptivo o neuropatico o una combinacion de estos. El cuestionario de dolor "Pain detect" fue especificamente desarrollado para detectar los componentes del dolor neuropatico en adultos. El tratamiento del GRD mediante RFp con abordaje epidural realizado en los casos descritos ha demostrado ser efectivo. Hemos obtenido una buena tasa de exitos con una disminucion en la EVN de mas del 50 % en los dos casos, con la practica desaparicion del componente neuropatico del dolor. El abordaje a traves del canal epidural via translaminar aporta gran seguridad emergiendo como una opcion adecuada para disminuir la tasa de complicaciones graves. EnglishPulsed radiofrequency (pRF) has been used for the treatment of peripheral nerves and the dorsal root ganglion (DRG). It has been commonly applied for the treatment of low back pain, neck pain and neuropathies with very good results. The dorsal root ganglion is an anatomical structure that is located bilaterally at the distal end of the dorsal root in the lateral epidural space. Most of the thoracic GRDs are located in the medial cranial part of the intervertebral foramina. Patients with thoracic pain radiated following a segmental pattern, which do not respond to conservative treatment, are susceptible to treatment by pRF from the DRG. In order to overcome the technical difficulties in access to thoracic GRD and to minimize the possible iatrogenic complications derived from the traditional percutaneous technique, we decided to perform the pRF technique in GRD at the thoracic level with epidural catheter by approaching the epidural space via translaminar in two patients with thoracic radiculopathy. Treatment of the dorsal root ganglion at the lumbar level is a widespread therapy in patients with chronic low back pain. Various studies and reviews support the realization of this technique. However, thoracic radicular pain is not a typical clinical syndrome such as in the lumbar area. There are different pain patterns: constant or intermittent pain, nociceptive or neuropathic pain or a combination of these. The PAIN DETECT questionnaire was specifically developed to detect the components of neuropathic pain in adults. Treatment of DRG using pRF with an epidural approach performed in the cases described has been shown to be effective. We obtained a good success rate with a decrease in NRS of more than 50% in both cases, with the practical disappearance of the neuropathic component of pain. The approach through the epidural canal via translaminar provides great safety emerging as an adequate option to decrease the rate of serious complications.

Traditionally, the development and validation of computational measures of rhythmic similarity in music relies on proxy classification tasks, often equating rhythm similarity to genre. In this paper, we perform a comprehensive, cross-disciplinary exploration of the classification performance of a state-of-the-art system for rhythm similarity. By synthesizing the methods of quantitative analysis with a musicological perspective, detailed insight is gained into the various facets that affect system behaviour, consisting of three main areas: rhythmic sensitivities of a given feature representation, idiosyncrasies of the data used for evaluation, and the tenuous relationship between rhythmic similarity and genre. Through this study, we provide perspective on gauging the abilities of a computational system beyond classification accuracy, as well as a deeper understanding of system design and evaluation methodology as a musically meaningful exercise.

VSC based converters are among the most preferred interfaces to perform the interconnection, especially for integration of distributed energy sources, active filtering, and power supply applications. Hysteresis current control presents very attractive characteristics for these applications such as: robust control, fast dynamical response, built-in over-current protection and simple and reliable implementation. However, its highly nonlinear nature have been represented a challenge for the proposal of mathematical models to perform analysis and design tasks. This paper proposes a novel modeling approach based on the accurate calculation of the switching times for time and frequency analyses for grid interconnected hysteresis current controlled VSC converters. From this proposal, analytic formulations in the time domain and frequency domain of the harmonics generated by the controller are drawn. These can be useful to develop analysis and practical design methodologies based on numerical methods.

This paper proposes the use of the extended harmonic domain as modeling framework in the formulation of optimization problems to compute optimal designs in terms of specific characteristics of the system, such as power losses, cost, size, among others. The overall advantages of use this modeling tool are the explicit consideration of the switching process and its harmonic effects in the formulation. As result, an optimization problem, in which the operating conditions and power quality requirements are explicitly stated as nonlinear restrictions of the problem, is obtained. A case study aimed to minimize the losses of an L-filter based active rectifier is presented, in order to give more detail in the implementation of this proposal. The obtained results show the evolution of the variables involved in the optimal design for several cases as the switching frequency varies. From these results, the optimal switching frequency could be selected along with its optimal design characteristics.

El dolor neuropático es un grupo heterogéneo de condiciones dolorosas causadas por lesión o enfermedad del sistema nervioso central o periférico. La Asociación Internacional de Estudio del Dolor (IASP) lo definió como “el dolor que sigue a una lesión primaria o disfunción del sistema nervioso central o periférico”. Recientemente, esta misma asociación lo ha redefinido como "aquel que se presenta como consecuencia directa de lesión o enfermedad y que afecta al sistema somatosensorial". A menudo tiene un impacto negativo sobre la salud mental y sobre la calidad de vida. Existen varias líneas farmacológicas para el tratamiento del dolor neuropático: antidepresivos, antiepilépticos y opioides conforman el tratamiento clásico. También disponemos de técnicas intervencionistas que habitualmente se aplican en pacientes con dolor neuropático rebelde a tratamiento farmacológico (bloqueos nerviosos periféricos, radiofrecuencia, toxina botulínica, etc.). Debido a que muchos de los pacientes están tratados con un único tratamiento pero no llegan a obtener alivio satisfactorio del dolor, las guías clínicas enfatizan que se pueden beneficiar del uso de combinaciones de medicaciones eficaces. Sin embargo, a pesar de estas estrategias, en ocasiones ni la combinación de tratamientos farmacológicos orales ni el uso de técnicas intervencionistas es totalmente eficaz.

This paper presents an educational tool based on a novel approach to develop an FPGA-based real-time emulator of an induction motor using the dynamic model. The method exploits the parallelism and high speed characteristics of the FPGA. Different fixed-point representation of the external and internal signal is used. The emulator architecture is presented as well as peripheral units implemented along with the main unit. The real-time emulator is evaluated by experimentation under start-up and varaible load torque conditions. This emulator is the based to implement algorithms like speed and flux estimators, i. e. Extended Kalman Filter, Luenberguer-like observer, etc., and several control schemes like Direct Torque Control, Field-Oriented Control, etc. for induction motors.

In this work it is presented the case peculiar of the design and the construction of a table of coordinates using optic sensors as way of control. This prototype arises like an educational strategy, through which is sought that the students of the first years of the careers of Engineering in the Polytechnic University of San Luis Potosi feels incorporate to a concrete project in which they integrate the acquired knowledge to the beginning of its professional formation.

To show the advantages of the use of vaginal misoprostol, a prostaglandine E1 analogue, in the prevention of the post-partum haemorrhage.This was a prospective, observational, comparative study. The study included 400 patients with high risk of postpartum haemorrhage at our center between January 1999 and may 2001. Patients were divided in two groups. In group I (208 patients) misoprostol was used in a dose of 800 ugr and in group II (192 patients) in whom misoprostol was not used. Both groups were treated initially with our conventional oxytocin protocol. We evaluated the use of additional oxytocin or ergotamine, haemoglobin levels pre and post-partum, the amount of blood loss, and the need for blood transfusion or hysterectomy.The need for additional oxytocin or ergotamine was reduced to less than 10% in group I when compared to group II; the drop in haemoglobin levels and the amount of blood loss were also less in group I (p: 0.03). In this group only one patient needed for blood transfusion and no patient needed hysterectomy. In group II six patients need a blood transfusion and there was the need for two hysterectomies.The use of vaginal misoprostol is effective to control the postpartum bleeding, reducing the blood loss after birth in women with high risk of post-partum haemorrhage as well as the need for blood transfusion. It's use has mild side effects and is of low cost.

Las sequías son fenómenos ambientales a losque se les han adjuntado una serie de fenómenossociohistóricos de orden ideológico y operativoque han intensificado y producido la escasezde agua que actualmente viven las grandesciudades. El presente documento tiene la intenciónde mostrar qué es el fenómeno de la sequía,cómo se manifiesta una sequía, cuáles son losdaños que provoca, qué acciones implementael gobierno para combatirla, de qué manera sepodría resolver este problema en el futuro y dequé forma se representa este fenómeno enMéxico.