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In this paper, we present integrated lead-free energy converters based on a suitable MEMS fabrication process with an embedded layer of LiNbO3. The fabrication technology has been developed to realize micromachined self-generating transducers to convert kinetic energy into electrical energy. The process proposed presents several interesting features with the possibility of realizing smaller scale devices, integrated systems, miniaturized mechanical and electromechanical sensors, and transducers with an active layer used as the main conversion element. When the system is fabricated in the typical cantilever configuration, it can produce a peak-to-peak open-circuit output voltage of 0.208 V, due to flexural deformation, and a power density of 1.9 nW·mm−3·g−2 at resonance, with values of acceleration and frequency of 2.4 g and 4096 Hz, respectively. The electromechanical transduction capability is exploited for sensing and power generation/energy harvesting applications. Theoretical considerations, simulations, numerical analyses, and experiments are presented to show the proposed LiNbO3-based MEMS fabrication process suitability. This paper presents substantial contributions to the state-of-the-art, proposing an integral solution regarding the design, modelling, simulation, realization, and characterization of a novel transducer.

Background: Psoriasis in children and adolescents has not been well studied in Mexico. Objective: To study the epidemiological characteristics of psoriasis in this age group. Methods: This is a retrospective study in an academic, tertiary care dermatology center from January 1999 to December 2014. We included patients ≤ 18 years of age, with clinical and histopathological diagnosis of psoriasis. We recorded the following information: gender, age, disease duration, clinical variant, nail involvement, treatment, and family history. Descriptive and inferential statistics were used for analysis. Results: Of 2,491 patients with psoriasis, 280 were ≤ 18 years of age, resulting in a prevalence of 11%. There was female predominance and the mean age was 11.5 years. Disease duration was 18 ± 34 months. Plaque psoriasis was the most common form, comprising 191 cases (68%). Nail involvement occurred in only 15 patients (5%). Topical treatment was given to 177 patients (63%). Only 14 cases (5%) had a family history of psoriasis. These variables did not differ when children were compared with adolescents, except in those with a shorter disease duration (13 ± 19 vs. 24 ± 29 months; p = 0.0004). Conclusions: We found a higher prevalence of psoriasis than previously published studies in this age group and a lower frequency of nail involvement and family history of psoriasis. (Rev Inves ClIn. 2017;69:47-50)

In this paper, we present integrated lead-free energy converters based on a suitable MEMS fabrication process with an embedded layer of LiNbO3. The fabrication technology has been developed to realize micromachined self-generating transducers to convert kinetic energy into electrical energy. The process proposed presents several interesting features with the possibility of realizing smaller scale devices, integrated systems, miniaturized mechanical and electromechanical sensors, and transducers with an active layer used as the main conversion element. When the system is fabricated in the typical cantilever configuration, it can produce a peak-to-peak open-circuit output voltage of 0.208 V, due to flexural deformation, and a power density of 1.9 nW·mm−3·g−2 at resonance, with values of acceleration and frequency of 2.4 g and 4096 Hz, respectively. The electromechanical transduction capability is exploited for sensing and power generation/energy harvesting applications. Theoretical considerations, simulations, numerical analyses, and experiments are presented to show the proposed LiNbO3-based MEMS fabrication process suitability. This paper presents substantial contributions to the state-of-the-art, proposing an integral solution regarding the design, modelling, simulation, realization, and characterization of a novel transducer.