Aproximació a la mesura ECTS i disseny de mecanismes d’avaluació de les competències socio-profesionals a l’Enginyeria Tècnica Industrial

Aquest treball és el resultat d'una primera experiència de coordinació entre professors per a la millora de la qualitat de la docència a les enginyeries tècniques de la Universitat de les Illes Balears, com també una experiència en la valoració qualitativa i quantitativa del crèdit ECTS. El treball vol mostrar els mecanismes per quantificar el nombre d’hores reals que l’alumne ha dedicat als estudis, i contrastar-lo amb el rendiment que n’ha tret en el procés d’avaluació de totes les assignatures participants en el projecte, com també l’estimació de la càrrega que suposa per al professor. Combinat amb l’aproximació al crèdit ECTS, es mostren experiències en l’avaluació de competències socioprofessionals, sobretot per establir mecanismes objectivables per aconseguir una avaluació coherent per al professor i per a l’alumneEste trabajo es el resultado de una primera experiencia de coordinación entre profesores para la mejora de la calidad de la docencia dentro de las ingenierías técnicas de la Universitat de les Illes Balears, así como una experiencia en la valoración cualitativa y cuantitativa del crédito ECTS. El trabajo quiere mostrar los mecanismos para cuantificar el número de horas reales que el alumno ha dedicado en contraste con el rendimiento que ha obtenido a través del proceso de evaluación de todas las asignaturas participantes en el proyecto, así como la estimación de la carga que supone para el profesor. Combinado con la aproximación al crédito ECTS, se muestran experiencias en la evaluación de competencias socio-profesionales i sobretodo establecer mecanismos no subjetivos para conseguir una evaluación coherente para el profesor i para el alumno

Human Milk Feeding for Septic Newborn Infants Might Minimize Their Exposure to Ventilation Therapy

Background. It has been well established that human milk feeding contributes to limiting lung diseases in vulnerable neonates. The primary aim of this study was to compare the need for mechanical ventilation between human milk-fed neonates with sepsis and formula-fed neonates with sepsis. Methods. All late preterm and full-term infants from a single center with sepsis findings from 2002 to 2017 were identified. Data on infant feeding during hospital admission were also recorded. Multivariate logistic regression analyses were performed to assess the impact of feeding type on ventilation support and main neonatal morbidities. Results. The total number of participants was 322 (human milk group = 260; exclusive formula group = 62). In the bivariate analysis, 72% of human milk-fed neonates did not require oxygen therapy or respiratory support versus 55% of their formula-fed counterparts (p < 0.0001). Accordingly, invasive mechanical ventilation was required in 9.2% of any human milk-fed infants versus 32% of their exclusively formula-fed counterparts (p = 0.0085). These results held true in multivariate analysis; indeed, any human milk-fed neonates were more likely to require less respiratory support (OR = 0.44; 95% CI:0.22, 0.89) than those who were exclusively formula-fed. Conclusion. Human milk feeding may minimize exposure to mechanical ventilation

Ultrasensitive mass sensor fully integrated with complementary metal-oxide-semiconductor circuitry

Nanomechanical resonators have been monolithically integrated on preprocessed complementary metal-oxide-semiconductor(CMOS) chips. Fabricatedresonatorsystems have been designed to have resonance frequencies up to 1.5 MHz. The systems have been characterized in ambient air and vacuum conditions and display ultrasensitive mass detection in air. A mass sensitivity of 4ag/Hz has been determined in air by placing a single glycerine drop, having a measured weight of 57 fg, at the apex of a cantilever and subsequently measuring a frequency shift of 14.8 kHz. CMOS integration enables electrostatic excitation, capacitive detection, and amplification of the resonance signal directly on the chip

Breastfeeding disparities between multiples and singletons by NICU discharge

Multiple pregnancy increases the risk of a range of adverse perinatal outcomes, including breastfeeding failure. However, studies on predictive factors of breastfeeding duration in preterm twin infants have a conflicting result. The purpose of this observational study was to compare feeding practices, at hospital discharge, of twin and singleton very low birth weight infants. The study is part of a prospective survey of a national Spanish cohort of very low birth weight infants (SEN1500) that includes 62 neonatal units. The study population comprised all infants registered in the network from 2002 to 2013. They were grouped into singletons and multiples. The explanatory variables were first analyzed using univariate models; subsequently, significant variables were analyzed simultaneously in a multiple stepwise backward model. During the twelve-year period, 32,770 very low birth weight infants were included in the database, of which 26.957 were discharged alive and included in this analysis. Nine thousand seven hundred and fifty-eight neonates were multiples, and 17,199 were singletons. At discharge, 31% of singleton infants were being exclusively breastfed, 43% were bottle-fed, and 26% were fed a combination of both. In comparison, at discharge, only 24% of multiple infants were exclusively breastfed, 43% were bottle-fed, and 33% were fed a combination of both (p < 0.001). On multivariable analysis, twin pregnancy had a statistically significant, but small efect, on cessation of breastfeeding before discharge (OR 1.10; 95% CI: 1.02, 1.19). Risks of early in-hospital breastfeeding cessation were also independently associated with multiple mother-infant stress factors, such as sepsis, intraventricular hemorrhage, retinopathy, necrotizing enterocolitis, intubation, and use of inotropes. Instead, antibiotic treatment at delivery, In vitro fertilization and prenatal steroids were associated with a decreased risk for shorter in-hospital breastfeeding duration. Multiple pregnancy, even in the absence of pathological conditions associated to very low birth weight twin infants, may be an impeding factor for in-hospital breastfeeding

NEMS/CMOS sensor for monitoring deposition rates in stencil lithography

A nanoelectromechanical mass sensor is used to characterize material deposition rates in stencil lithography. The material flux through micron size apertures is mapped with high spatial (below 1 μm) and deposition rate (below 10 pm/s) resolutions by displacing the stencil apertures over the sensor. The sensor is based on a resonating metallic beam (with submicron size width and thickness) monolithically integrated with a CMOS circuit, resulting in a CMOS/NEMS self-oscillator. The sensor is used to test alignment for multi-level nanostencil lithography

Development of CMOS-MEMS/NEMS Devices

Micro and nano-electro-mechanical system (M/NEMS) devices constitute key technological building blocks to enable increased additional functionalities within Integrated Circuits (ICs) in the More-Than-Moore era, as described in the International Technology Roadmap for Semiconductors. The CMOS ICs and M/NEMS dies can be combined in the same package (SiP), or integrated within a single chip (SoC). In the SoC approach the M/NEMS devices are monolithically integrated together with CMOS circuitry allowing the development of compact and low-cost CMOS-M/NEMS devices for multiple applications (physical sensors, chemical sensors, biosensors, actuators, energy actuators, filters, mechanical relays, and others). On-chip CMOS electronics integration can overcome limitations related to the extremely low-level signals in sub-micrometer and nanometer scale electromechanical transducers enabling novel breakthrough applications. This Special Issue aims to gather high quality research contributions dealing with MEMS and NEMS devices monolithically integrated with CMOS, independently of the final application and fabrication approach adopted (MEMS-first, interleaved MEMS, MEMS-last or others).

Editorial for the Special Issue on Development of CMOS-MEMS/NEMS Devices

Micro and nanoelectromechanical system (M/NEMS) devices constitute key technological building blocks to enable increased additional functionalities within integrated circuits (ICs) in the More-Than-Moore era, as described in the International Technology Roadmap for Semiconductors [...

Monolithic CMOS-MEMS resonant beams for ultrasensitive mass detection

Consultable des del TDXTítol obtingut de la portada digitalitzadaEstructures ressonants en forma de biga (p.e. ponts o palanques) són molt interessants com a element transductor en sensors físics, químics i biològics basats en sistemes micro-/nanoelectromecànics (M-/NEMS) degut a la seva simplicitat, al gran rang de dominis que poden sensar, i a la seva extremada alta sensibilitat. Aquesta tesis està focalitzada en el disseny, fabricació i caracterització de CMOS-MEMS monolítics basats en bigues ressonants a escala sub-micromètrica per a la seva utilització en la detecció ultra sensible de massa amb un dispositiu portable. Els ressonadors operen en mode dinàmic on la massa es mesurada com un canvi de la seva freqüència de ressonància que és induïda electrostàticament i llegida d'una forma capacitiva mitjançant un circuit CMOS integrat monolíticament. Dues aproximacions tecnològiques diferents són considerades per tal de fabricar bigues ressonants a escala sub-micromètrica sobre xips CMOS prèviament processats, possibilitant una integració monolítica: (i) post processant els xips CMOS amb tècniques de nano fabricació per obtenir les estructures ressonants o (ii) definint els ressonadors al mateix temps que els circuits CMOS. Per les dues aproximacions, es presenten dispositius de metall i de polysilici amb sensibilitats de massa sense precedents (per a sensors CMOS monolítics) dins el rang dels atto-/zeptograms. Es presenta una comparativa dels resultats aconseguits mitjançant les dues aproximacions tecnològiques. Es dissenyen circuits de lectura CMOS d'alta sensibilitat per amplificar el corrent capacitiu amb guanys de transimpedància (utilitzant una tecnologia comercial CMOS 0.35-μm) de fins a 120 dBΩ a 10 MHz possibilitant la detecció del desplaçament del ressonador amb resolucions de fins a ~10 fm/√Hz semblants a les obtingudes pels millors sistemes de detecció òptics reportats i sense la necessitat d'un equipament complexa. Es presenta la caracterització elèctrica, a l'aire i al buit, de dispositius CMOS-MEMS fabricats que corroboren la capacitat de l'aproximació monolítica presentada per mesurar la característica freqüencial de ressonadors a escala sub-micromètrica. S'aconsegueix una transducció electrostàtica òptima i es mesuren respostes freqüencials elèctriques amb pics elevats (fins a 20 dB o més) i grans canvis de fase (fins a 160º) al voltant de la freqüència de ressonància. També es reporten mesures on s'observen efectes de softening/harderning de la constant de molla i d'histèresis produïts per les no linealitats així com la detecció del moviment Brownià intrínsec demostrant el bon matching de soroll entre el ressonador i el circuit de lectura. També es presenten els resultats de calibració, de mesures en temps real, i d'anàlisi de la resolució dels dispositius fabricats obtenint valors de fins a ~30 zg/√Hz (equivalent a ~6 pg/cm2√Hz) en condicions de buit que indiquen la millora respecte a treballs anteriors en termes de sensibilitat, resolució i procés de fabricació. Es presenta i es testeja un circuit oscil·lador Pierce CMOS adaptat per a treballar amb ressonadors de ~10 MHz i amb resistències mecàniques equivalents de fins a 100 MΩ demostrant que és factible la detecció d'attograms amb un dispositiu sensor completament portable.Resonant beams structures are very attractive transducers for physical, chemical and biological sensors based on micro-/nanoelectromechanical systems (M-/NEMS) due to its simplicity, wide range of sensing domains, and extremely high sensitivity. This Ph.D. thesis is focused on the design, fabrication and characterization of monolithic CMOS-MEMS based on sub-micrometer scale resonant beams for its application in ultrasensitive mass detection with a portable device. The resonators operate in dynamic mode where the mass is measured as a change of its resonant frequency which is electrostatically induced and capacitive readout by means of a monolithically integrated CMOS circuitry. Two different technological approaches are considered to fabricate sub-micrometer scale resonant beams on pre-processed CMOS chips allowing a monolithic integration: (i) nano post-processing of the CMOS chip to obtain the resonant beams or (ii) definition of the resonant beams at the same time that the CMOS circuits. From both approaches, metal and polysilicon devices exhibiting unprecedented mass sensitivities (for monolithic CMOS sensors) in the atto-/zeptogram range are reported. Comparison of the results following both approaches is given. High-sensitivity readout CMOS circuits are specifically designed to amplify the capacitive current with transimpedance gains (using a commercial 0.35-μm CMOS technology) up to 120 dBΩ at 10 MHz allowing to detect the resonator displacement with resolutions up to ~10 fm/√Hz which are similar than the best reported optical readout systems without the need of a bulky setup. Electrical characterization, in air and in vacuum conditions, of fabricated CMOS-MEMS devices is presented corroborating the ability of the presented monolithic approach in measuring the frequency characteristics of sub-micrometer scale beam resonators. Optimal electrostatic transduction is achieved measuring electrical frequency responses with high peaks (up to 20 dB or more) and large phase shifts (up to 160º) around the resonance frequency. Measurements showing soft/hard-spring effect and hysteretic performance due to nonlinearities are also reported as well as the detection of intrinsic Brownian motion demonstrating the noise-matching between the resonator and the readout circuit. Results from calibration, real time mass measurements, and resolution analysis on fabricated devices obtaining values down to ~30 zg/√Hz (equivalent to ~6 pg/cm2√Hz) in vacuum conditions are also reported indicating the improvement from previous works in terms of sensitivity, resolution, and fabrication process. A specific CMOS Pierce oscillator circuit adapted to work with ~10 MHz beam resonators showing motional resistance up to 100 MΩ is presented and tested demonstrating the feasible attogram detection with a completely portable sensor device

Conversa amb Joaquín Araujo

Joaquín Araújo es escritor, guionista y realizador cinematográfico, periodista, geógrafo y agricultor, pero todo ello centrado y vinculado con la naturaleza.Vinculado con los movimientos ecologistas, es miembr del Consejo asesor de Medio ambiente y presidente de Ecofórum. La entrevista recoge su biografía y comentarios sobre la degradación ambiental y el empobrecimiento cultural que marcan los tiempos modernos. Señala la necesidad y urgencia de que el hombre cambie su actitud hacia el propio ser humano y hacia la naturaleza. Propugna la cofundación del mundo, la necesidad de explicarlo más que dirigirlo.BalearesES

Thermomechanical Noise Characterization in Fully Monolithic CMOS-MEMS Resonators

We analyzed experimentally the noise characteristics of fully integrated CMOS-MEMS resonators to determine the overall thermomechanical noise and its impact on the limit of detection at the system level. Measurements from four MEMS resonator geometries designed for ultrasensitive detection operating between 2-MHz and 8-MHz monolithically integrated with a low-noise CMOS capacitive readout circuit were analyzed and used to determine the resolution achieved in terms of displacement and capacitance variation. The CMOS-MEMS system provides unprecedented detection resolution of 11 yF&middot;Hz&minus;1/2 equivalent to a minimum detectable displacement (MDD) of 13 fm&middot;Hz&minus;1/2, enabling noise characterization that is experimentally demonstrated by thermomechanical noise detection and compared to theoretical model values