Global design of analog cells using statistical optimization techniques

We present a methodology for automated sizing of analog cells using statistical optimization in a simulation based approach. This methodology enables us to design complex analog cells from scratch within reasonable CPU time. Three different specification types are covered: strong constraints on the electrical performance of the cells, weak constraints on this performance, and design objectives. A mathematical cost function is proposed and a bunch of heuristics is given to increase accuracy and reduce CPU time to minimize the cost function. A technique is also presented to yield designs with reduced variability in the performance parameters, under random variations of the transistor technological parameters. Several CMOS analog cells with complexity levels up to 48 transistors are designed for illustration. Measurements from fabricated prototypes demonstrate the suitability of the proposed methodology

PMCTrack: Delivering performance monitoring counter support to the OS scheduler

Hardware performance monitoring counters (PMCs) have proven effective in characterizing application performance. Because PMCs can only be accessed directly at the OS privilege level, kernellevel tools must be developed to enable the end-user and userspace programs to access PMCs. A large body of work has demonstrated that the OS can perform effective runtime optimizations in multicore systems by leveraging performance-counter data. Special attention has been paid to optimizations in the OS scheduler. While existing performance monitoring tools greatly simplify the collection of PMC application data from userspace, they do not provide an architecture-agnostic kernel-level mechanism that is capable of exposing high-level PMC metrics to OS components, such as the scheduler. As a result, the implementation of PMC-based OS scheduling schemes is typically tied to specific processor models. To address this shortcoming we present PMCTrack, a novel tool for the Linux kernel that provides a simple architecture-independent mechanism that makes it possible for the OS scheduler to access per-thread PMC data. Despite being an OSoriented tool, PMCTrack still allows the gathering of monitoring data from userspace, enabling kernel developers to carry out the necessary offline analysis and debugging to assist them during the scheduler design process. In addition, the tool provides both the OS and the user-space PMCTrack components with other insightful metrics available in modern processors and which are not directly exposed as PMCs, such as cache occupancy or energy consumption. This information is also of great value when it comes to analyzing the potential benefits of novel scheduling policies on real systems. In this paper, we analyze different case studies that demonstrate the flexibility, simplicity and powerful features of PMCTrack.Facultad de InformáticaInstituto de Investigación en Informátic

PMCTrack: Delivering performance monitoring counter support to the OS scheduler

Hardware performance monitoring counters (PMCs) have proven effective in characterizing application performance. Because PMCs can only be accessed directly at the OS privilege level, kernellevel tools must be developed to enable the end-user and userspace programs to access PMCs. A large body of work has demonstrated that the OS can perform effective runtime optimizations in multicore systems by leveraging performance-counter data. Special attention has been paid to optimizations in the OS scheduler. While existing performance monitoring tools greatly simplify the collection of PMC application data from userspace, they do not provide an architecture-agnostic kernel-level mechanism that is capable of exposing high-level PMC metrics to OS components, such as the scheduler. As a result, the implementation of PMC-based OS scheduling schemes is typically tied to specific processor models. To address this shortcoming we present PMCTrack, a novel tool for the Linux kernel that provides a simple architecture-independent mechanism that makes it possible for the OS scheduler to access per-thread PMC data. Despite being an OSoriented tool, PMCTrack still allows the gathering of monitoring data from userspace, enabling kernel developers to carry out the necessary offline analysis and debugging to assist them during the scheduler design process. In addition, the tool provides both the OS and the user-space PMCTrack components with other insightful metrics available in modern processors and which are not directly exposed as PMCs, such as cache occupancy or energy consumption. This information is also of great value when it comes to analyzing the potential benefits of novel scheduling policies on real systems. In this paper, we analyze different case studies that demonstrate the flexibility, simplicity and powerful features of PMCTrack.Facultad de InformáticaInstituto de Investigación en Informátic

Las alternativas ciudadanas emergentes en Jalisco

El documento hace una descricpión, clasificación temática y análisis de las alternativas o iniciativas ciudadanas localizadas en el estado de Jalisco, México. Los proyectos impulsados por iniciativas ciudadanas tienen como propósito la sustentabilidad, el desarrollo económico y social, la artiuclación del tejido social, la eficiencia y redefinición de las instituciones públicas, la reforma del pensamiento y la educación, y los proyectos alternativos integrales. El análisis que se hace sobre esos proyectos se centra en el perfíl de sus participantes, las relaciones o articulación que se dan entre esas iniciativas y la manera como se relacionan con las instituciones públicas.ITESO, A.C

Sal k 5, a member of the widespread Ole e 1-like protein family, is a new allergen of Russian thistle (Salsola kali) pollen.

Salsola kali is an Amaranthaceae weed with important repercussions for pollinosis in temperate areas. Ole e 1-like members are relevant allergens in pollen from different species. We aimed to characterize and produce as recombinant allergen S. kali Ole e 1-like protein. METHODS:The natural allergen was purified at homogeneity after three chromatographic steps. Specific cDNA was sequenced and expressed in Pichia pastoris yeast. Structural relationships of natural and recombinant forms were carried out by 2D electrophoresis and spectroscopic analyses. Its immunological relevance was analyzed by ELISA and immunoblotting using an IgG antiserum and monoclonal antibodies specific to Ole e 1, as well as sera from 57 allergic patients recruited from two Spanish regions where this pollinosis is frequent. RESULTS:The purified allergen, Sal k 5, is an acidic glycoprotein of 151 amino acid residues and 17,628 Da of molecular mass. Its amino acid sequence exhibits 68 and 32% identity with the allergens of Che a 1 and Ole e 1, respectively. The recombinant protein was correctly processed and its structural and immunologic equivalence to the natural form was proven. A sensitization frequency between 30 and 40% was observed in pollinic patients from the center and east coast of Spain. CONCLUSIONS:Sal k 5 is a member of the Ole e 1-like protein family which can be considered an important allergen from S. kali. Its inclusion in diagnosis protocols would allow the accurate defining of patients allergic to this pollen

Diabetes and atypical presentations of patients hospitalized for an acute myocardial infarction in Puerto Rico

Introduction: Diabetes mellitus is one of the fastest growing health issues concerning the world today with an estimated 382 million individuals affected as of 2013 and a projected increase in number to 592 million by 2035. Diabetes mellitus is a condition affecting 12-15% of the population or around 400,000 people in Puerto Rico. The most common presenting complaint of diabetics who are hospitalized for an acute myocardial infarction (AMI) is chest pain. However, the pervasiveness of atypical symptoms in diabetic patients is yet unclear. The aim of this study is to determine if there is an association between diabetes and the presentation of atypical symptoms in the emergency room in those suffering from an AMI in Puerto Rico. Methods: We conducted a secondary data analysis of data from participants from the 2007, 2009 and 2011 Puerto Rico Cardiovascular Disease Surveillance system (PRCDS), an observational, non-concurrent, cross-sectional study. The main independent variable was presence of diabetes mellitus (Type I and Type II). The outcome was the presence of atypical symptoms at the time of presentation, defined as the absence of chest pain on admission. The prevalence of atypical symptoms in diabetic patients and non-diabetic patients was compared. Binary logistic regression was used to test for independent association. Statistical significance was considered for p-values ≤0.05 for a two-tailed test. Analysis was conducted using SPSS software. Results: We found no association between atypical presentation of an AMI and diabetes, before or after adjustment for age, gender, congestive heart failure, stroke history and BMI. (unadjusted OR= 1.0, 95%CI=0.7-1.4 and adjusted OR=1.0, 95% CI=0.6-1.5). Other independent associations identified were that patients older than 75 were 3.5 times more likely to present atypically than people younger than 55 (OR= 3.5, 95% CI=1.6-7.6), and those with CHF and stroke were more likely to present with atypical symptoms (OR=3.2, 95% CI=1.7-6.1 and OR=4.2 95% CI=2.1-8.4, respectively). Lastly, overweight patients were 3.3 times more likely to present atypically than healthy weight patients (OR=2.0, 95% CI=0.6-7.0). Conclusion: We found no evidence of an association between diabetes and the presentation of atypical symptoms in patients hospitalized for AMI in Puerto Rico

Apuntes para las clases virtuales que demanda la formación online de ingenieros y licenciados en plataformas Moodle

Con el aumento constante de la virtualidad ha continuado evolucionando el empleo de las plataformas digitales con la preocupación de una formación sólida de los ingenieros y licenciados. El estudio acerca del empleo de las Plataformas Moodle evidencia la necesidad de establecer un adecuado balance entre las actividades y los recursos, con atención al aporte de cada una. En particular se requiere del Taller o Fórum y de Archivos Multimedia para actividades demostrativas e indicar la realización de ejercicios prácticos de simulación que guíen el desarrollo de las competencias afines al perfil de formación del ingeniero o del licenciado.With the constant increase in virtuality, the use of digital platforms has continued to evolve with the concern of a solid training of engineers and graduates. The study on the use of Moodle Platforms shows the need to establish an adequate balance between activities and resources, paying attention to the contribution of each one. In particular, the Workshop or Forum and Multimedia Files are required for demonstration activities and indicate the realization of practical simulation exercises that guide the development of skills related to the training profile of the engineer or graduate

A CMOS 0.8 μm fully differential current mode buffer for HF SI circuits

El pdf del artículo es la versión post-print.We present a high-frequency fully-differential current-mode buffer to interface off-chip currents with no significant degradation of the frequency response, and to measure current-mode ICs using standard equipment. It has been fabricated in a 0.8μm double-poly double-metal CMOS technology and features more than 37MHz bandwidth. In order to show its functionality, this unit has been incorporated to the front end of a Switched-Current Band-Pass ΣΔ modulator featuring 9 bit dynamic range at 10MHz clock frequency for a 30kHz signal bandwidth centered at 2.5MHz.Peer reviewe

Nanostructured multilayer compartments : towards multifunctionality and ‘‘cell-like’’ hierarchical complexity

In living organisms, there are phenomena that require the presence of specific biomolecules with distinct function and in variable concentrations at a given time, such as the healing and regeneration of tissue and organ lesions. In this work, we propose the use of a compartmented drug delivery device for the multiple release of bioactive agents. It consists of nanostructured microcapsules confined within a millimetric container that can be easily handled, mimicking the concept of cells which possess organelles with specialized functions. Each hierarchical structure was conceived using the layer-by-layer (LbL) method to form micro and macrocapsules that could individually carry either molecules and release them with distinct kinetics or magnetic nanoparticles (MNPs) to be used in targeted therapies. Furthermore, the internal microcontainers were constructed with a temperature-responsive elastin-like recombinamer (ELR) to further add smart properties to the proposed system. Sacrificial CaCO3 microparticles empty or entrapping either rhodamine or Fe3O4 MNPs were incubated in chitosan and ELR solutions using LbL for the conception of the microcapsules. Then, the microcapsules were suspended in alginate which was ionically crosslinked in CaCl2 drop-wise. Rhodamine could be encapsulated at this point in the alginate. The bead was coated with chitosan and alginate to build the external macrocapsule compartment. All structures were coated with 3 bilayers. The CaCO3 cores were chelated and the alginate beads liquefied using EDTA. Fluorescence microscopy using FITC and rhodamine markers showed a uniform distribution of the microcapsules within the macroreservoir. The release of rhodamine from either in the micro or macrocapsule was assessed at 25 and 37 °C in PBS. While the release from the macrocapsule follows a profile similar to that of traditional drug delivery systems, it is more sustained and delayed when released from the internal compartments. Such retention is more pronounced at 37 ºC (65% of release in comparison to 90%). This is due to the temperature responsive behavior of ELRs, which undergo a phase transition and make the LbL shell less permeable. For the magnetic response, the incorporation of the MNPs was observed by transmitted light microscopy. The attraction of the devices was observed by applying an external magnetic field along a defined trajectory. The results let foresee the use of such multilayer devices as compartmented structures to encapsulate growth factors, MNPs and stem cells for their controlled differentiation and maintenance or for guided regeneration of tissues and organs.Fundo Social Europeu (FSE)Fundação para a Ciência e a Tecnologia (FCT)Programa Diferencial de Potencial Humano (POPH