1,324 research outputs found

    Designing optimal discrete-feedback thermodynamic engines

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    Feedback can be utilized to convert information into useful work, making it an effective tool for increasing the performance of thermodynamic engines. Using feedback reversibility as a guiding principle, we devise a method for designing optimal feedback protocols for thermodynamic engines that extract all the information gained during feedback as work. Our method is based on the observation that in a feedback-reversible process the measurement and the time-reversal of the ensuing protocol both prepare the system in the same probabilistic state. We illustrate the utility of our method with two examples of the multi-particle Szilard engine.Comment: 15 pages, 5 figures, submitted to New J. Phy

    Deep-compact-clustering based anomaly detection applied to electromechanical industrial systems

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    The rapid growth in the industrial sector has required the development of more productive and reliable machinery, and therefore, leads to complex systems. In this regard, the automatic detection of unknown events in machinery represents a greater challenge, since uncharacterized catastrophic faults can occur. However, the existing methods for anomaly detection present limitations when dealing with highly complex industrial systems. For that purpose, a novel fault diagnosis methodology is developed to face the anomaly detection. An unsupervised anomaly detection framework named deep-autoencoder-compact-clustering one-class support-vector machine (DAECC-OC-SVM) is presented, which aims to incorporate the advantages of automatically learnt representation by deep neural network to improved anomaly detection performance. The method combines the training of a deep-autoencoder with clustering compact model and a one-class support-vector-machine function-based outlier detection method. The addressed methodology is applied on a public rolling bearing faults experimental test bench and on multi-fault experimental test bench. The results show that the proposed methodology it is able to accurately to detect unknown defects, outperforming other state-of-the-art methods.Peer ReviewedPostprint (published version

    Experiments on torrefaction of Dichrostachys cinerea wood: two-level factorial design and thermogravimetric analysis

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    The aim of this study was to determine the effect of the temperature and reaction time variables on the solid yield and the increment of heating values and composition of torrefied Dichrostachys cinerea wood by using a factorial experiment design and thermogravimetric analysis. The significant factors were identified by means of a two-level factorial design type (22), for which the statistical software Design Expert version 10 was used. Torrefaction and thermogravimetric experimental runs were carried out in a fixed-bed reactor and thermobalance TGA–DTA, respectively. Torrefaction temperature, residence time and their interaction have a significant effect on solid yield, whilst the effect of the temperature was the only statistically significant factor on increment at a high heating value (HHV). The R-Squared values for both response variables were greater than 95% in each case. An increase in torrefied biomass was achieved at HHVs of 14.92 and 30.31% under the conditions of 120 min at 250 and 290 °C, respectively. Thermogravimetric characterisation and DTG–TG curves of the torrefied material suggest that the pre-treated material has been modified chemically and structurally.This research was financed by a doctoral scholarship from the Università Politecnica Delle Marche, Ancona, Italy, and supported by the Department of Chemical Engineering, University of Alicante, Alicante, Spain

    Fluoride removal from natural volcanic underground water by an electrocoagulation process: Parametric and cost evaluations

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    The water supply on the island of Tenerife (Canary Islands, Spain) comes mainly from aquifers of volcanic origin that are notable for the high content of fluorides that make it unviable for human consumption without prior conditioning treatment. The treatments that generate a high rejection of water are not viable, since water is a scarce natural resource of high value. An electrocoagulation process was investigated as a method to treat natural groundwater from volcanic soils containing a dangerously high fluoride content. The operating parameters of an electrocoagulation reactor model with parallel plate aluminum electrodes were optimized for batch and continuous flow operations. In the case of batch operation, it was found that acidification of the water improved fluoride elimination efficiency, with a maximum at pH 3. Yet, operation at the natural pH of the water achieved elimination efficiencies between 82 and 92% depending on the applied current density. An optimum current density of 5 mA/cm2 was found in terms of the highest removal efficiency, and the kinetics of fluoride removal was adjusted to a pseudo-second-order kinetics. In the continuous-flow operation, with an optimal residence time of 10 min and a separation of 0.5 cm between the electrodes, it was observed that the current density that would be applied would depend on the initial concentration of fluoride in the raw water. Then, an initial fluoride concentration of 6.02 mg/L required a current density > 7.5 mA/cm2 to comply with the legal guidelines in the product water, while for an initial concentration of 8.98 mg/L, the optimum current density was 10 mA/cm2. Under these operating conditions, the operating costs will vary between 0.20 and 0.26 €/m3 of treated wate

    Use of alumina sludge arising from an electrocoagulation process as functional mesoporous microcapsules for active corrosion protection of aluminum

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    The process of fluoride removal from underground water using the electrocoagulation technique with aluminum electrodes results in the generation of large amounts of drinking-water treatment sludge (DWTS) corresponding to electrocoagulated metal hydroxide sludge (EMHS). EMHS, hazardous for the environment, must be adequately managed from the water treatment plant, causing an additional cost to the process and an environmental impact from its disposal. In this study, the revaluation of the EMHS produced using a laboratory scale electrocoagulation reactor with aluminum was investigated for the manufacture of mesoporous alumina microcapsules (MAMs). The obtained microcapsules have been characterized using X-ray diffractometry (XRD), scanning electron microscopy (SEM), Zeta-potential measurement, thermal gravimetric analysis (TGA), and Brunauer-Emmett-Teller (BET) techniques, allowing them to be classified as mesoporous particles of micro and nanometer dimensions. These particles were used as microcapsules to contain corrosion inhibitors (namely, 8-hydroxyquinoline and benzotriazole), and they were subsequently dispersed in a commercial polymer matrix employed to protect aluminum from the corrosive attack of the environment. The corrosion resistance of the resulting functionalized coatings has been characterized by electrochemical impedance spectroscopy (EIS) in the case of artificially-defective coatings, demonstrating that these MAM’s released locally the corrosion inhibitor to effectively heal the damaged area of the metal. The overall study demonstrates that the electrocoagulation sludge can be employed to produce microcapsules for efficient anticorrosion protection of engineering metals

    Role of estrogen related receptor beta (ESRRB) in DFN35B hearing impairment and dental decay

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    BACKGROUND: Congenital forms of hearing impairment can be caused by mutations in the estrogen related receptor beta (ESRRB) gene. Our initial linkage studies suggested the ESRRB locus is linked to high caries experience in humans. METHODS: We tested for association between the ESRRB locus and dental caries in 1,731 subjects, if ESRRB was expressed in whole saliva, if ESRRB was associated with the microhardness of the dental enamel, and if ESRRB was expressed during enamel development of mice. RESULTS: Two families with recessive ESRRB mutations and DFNB35 hearing impairment showed more extensive dental destruction by caries. Expression levels of ESRRB in whole saliva samples showed differences depending on sex and dental caries experience. CONCLUSIONS: The common etiology of dental caries and hearing impairment provides a venue to assist in the identification of individuals at risk to either condition and provides options for the development of new caries prevention strategies, if the associated ESRRB genetic variants are correlated with efficacy.Fil: Weber, Megan L.. University of Pittsburgh; Estados UnidosFil: Hsin, Hong Yuan. University of Pittsburgh; Estados UnidosFil: Kalay, Ersan. Karadeniz Technical University; TurquíaFil: Brožková, Dana Š. Charles University; República Checa. University Hospital Motol; República ChecaFil: Shimizu, Takehiko. Nihon University. School of Dentistry; JapónFil: Bayram, Merve. Medipol Istanbul University; TurquíaFil: Deeley, Kathleen. University of Pittsburgh; Estados UnidosFil: Küchler, Erika C.. University of Pittsburgh; Estados UnidosFil: Forella, Jessalyn. University of Pittsburgh; Estados UnidosFil: Ruff, Timothy D.. University of Pittsburgh; Estados UnidosFil: Trombetta, Vanessa M.. University of Pittsburgh; Estados UnidosFil: Sencak, Regina C.. University of Pittsburgh; Estados UnidosFil: Hummel, Michael. University of Pittsburgh; Estados UnidosFil: Briseño Ruiz, Jessica. University of Pittsburgh; Estados UnidosFil: Revu, Shankar K.. University of Pittsburgh; Estados UnidosFil: Granjeiro, José M.. Universidade Federal Fluminense; BrasilFil: Antunes, Leonardo S.. Universidade Federal Fluminense; BrasilFil: Antunes, Livia A.. Universidade Federal Fluminense; BrasilFil: Abreu, Fernanda V.. Universidade Federal Fluminense; BrasilFil: Costabel, Marcelo C.. Universidade Federal do Rio de Janeiro; BrasilFil: Tannure, Patricia N.. Veiga de Almeida University; Brasil. Salgado de Oliveira University; BrasilFil: Koruyucu, Mine. Istanbul University; TurquíaFil: Patir, Asli. Medipol Istanbul University; TurquíaFil: Poletta, Fernando Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas ; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mereb, Juan C.. Estudio Colaborativo Latino Americano de Malformaciones Congénitas; ArgentinaFil: Castilla, Eduardo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. CEMIC-CONICET. Centro de Educaciones Médicas e Investigaciones Clínicas ; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Orioli, Iêda M.. Universidade Federal do Rio de Janeiro; BrasilFil: Marazita, Mary L.. University of Pittsburgh; Estados UnidosFil: Ouyang, Hongjiao. University of Pittsburgh; Estados UnidosFil: Jayaraman, Thottala. University of Pittsburgh; Estados UnidosFil: Seymen, Figen. Istanbul University; TurquíaFil: Vieira, Alexandre R.. University of Pittsburgh; Estados Unido

    Near-Room-Temperature Reversible Giant Barocaloric Effects in [(CH₃)₄N]Mn[N₃]₃ Hybrid Perovskite

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    [Abstract] We report giant reversible barocaloric effects in [(CH₃)₄N]Mn[N₃]₃ hybrid organic–inorganic perovskite, near its first-order cubic-monoclinic structural phase transition at ₀ ∼ 305 K. When driving the transition thermally at atmospheric pressure, the transition displays a large change in entropy of ∼80 J K⁻¹ kg⁻¹ and a small thermal hysteresis of ∼7 K, as well as a large change in volume of ∼1.5%. When driving the transition with pressure near room temperature, the transition displays large changes in entropy of ∼70 J K⁻¹ kg⁻¹, which represent a giant barocaloric response. Hybrid perovskites with similar barocaloric response and lower operating temperatures may find applications in environmentally friendly cooling.The authors are grateful for financial support from Ministerio de Economía y Competitividad MINECO and EU-FEDER (MAT2017-86453-R), Xunta de Galicia (ED431G/09), FAMEPA (COOPI-07771/17), and ERC Starting Grant no. 680032Xunta de Galicia; ED431G/0

    Effect of central nervous system (CNS) metastases in a real-world multicenter cohort study of Spanish ALK-positive non-small cell lung cancer (NSCLC) patients (p)

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    Background: CNS is a common site of metastases in patients with ALK-positive NSCLC. CNS metastases are associated with a number of deleterious effects, such as reduction in quality of life. However, the relationship between brain metastases and prognosis remains unclear. We aimed to evaluate the effect of CNS metastases on overall survival (OS) in a multicenter cohort of Spanish ALK-positive NSCLC patients diagnosed between 2008 and 2017. Methods: We included patients with stage IV at diagnoses, followed up to April 2018; OS (months [m]) was estimated with the Kaplan-Meier method. Survival curves were compared between groups of patients using the log-rank test. Hazard risk (HR) to death was estimated with multivariable Cox model. Results: Out of 163 patients in the cohort, a total of 116 were evaluated, with a median of follow-up of 29.2 m and 59 deaths reported. Characteristics at diagnosis were a median age of 58 years, 50% female, 58.6% never-smokers, 54.3% with comorbidities, PS by ECOG 0-1 93.1%. CNS metastases (median number of lesions 6) were present in 43.1% of patients and 34% of patients with CNS metastases were treated with local therapy (11.8 % local radiotherapy and 76.5% holocraneal radiotherapy). ALK inhibitors as first line and second line treatment were administered to 45.5% and 78.6% of patients, respectively. The median OS was 39 months; OS in patients with CNS metastases at diagnosis was 34.4 m and 39.0 m in those without CNS metastases at diagnosis (p=.9). In patients without CNS metastases at baseline (n=60), 22 developed CNS, with a median OS greater than in those without CNS metastases during follow-up, although the difference is not significant (45.5 m vs 33.3 m; p=.9). There were 81 patients who presented with metastases in more than one organ and 33 patients with metastases in a single organ. The risk of death increased as the number of metastatic organs at diagnoses increased (HR=1.26, p=.0305), with worse OS in those presenting with liver metastases at diagnoses (21.1%, OS: 20 m), compared to those without tumor involvement (OS: 45.4 m; p =.008). Conclusions: OS was similar for ALK-positive NSCLC patients with and without CNS metastases at diagnoses. OS was worse as the number of metastatic organs at diagnosis increased, with liver metastases being associated with the highest risk of mortality

    Hypothalamic miR-30 regulates puberty onset via repression of the puberty-suppressing factor, Mkrn3.

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    Mkrn3, the maternally imprinted gene encoding the makorin RING-finger protein-3, has recently emerged as putative pubertal repressor, as evidenced by central precocity caused by MKRN3 mutations in humans; yet, the molecular underpinnings of this key regulatory action remain largely unexplored. We report herein that the microRNA, miR-30, with three binding sites in a highly conserved region of its 3' UTR, operates as repressor of Mkrn3 to control pubertal onset. Hypothalamic miR-30b expression increased, while Mkrn3 mRNA and protein content decreased, during rat postnatal maturation. Neonatal estrogen exposure, causing pubertal alterations, enhanced hypothalamic Mkrn3 and suppressed miR-30b expression in female rats. Functional in vitro analyses demonstrated a strong repressive action of miR-30b on Mkrn3 3' UTR. Moreover, central infusion during the juvenile period of target site blockers, tailored to prevent miR-30 binding to Mkrn3 3' UTR, reversed the prepubertal down-regulation of hypothalamic Mkrn3 protein and delayed female puberty. Collectively, our data unveil a novel hypothalamic miRNA pathway, involving miR-30, with a prominent role in the control of puberty via Mkrn3 repression. These findings expand our current understanding of the molecular basis of puberty and its disease states
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