Design methodology for an air-lubricated seal

A methodology to design an air-lubricated piston seal for pneumatic actuators is described. Such a seal permits a small air leakage through a very narrow gap between the seal lip and the counterpart; this air film both avoids contact and ensures lubrication at the seal-counterpart interface thus permitting reduced friction and wear. Subsequently the use of grease could be limited or avoided. A seal geometry equipped with a self-pressurized balancing chamber was designed to make leakage as insensitive as possible to the supply pressure and to the barrel machining tolerances. A prototype was manufactured and tests were carried ou

A Set-up for Static and Dynamic Characterization of Voltage and Current Transducers used in Railway Application

In the recent years, much more attention is paid to energy and power quality measurement in railway system. In both the case, the voltage and current transducers play a crucial role and their accuracy could determine the performance level of whole measurement system. To obtain reliable results, the accuracy of transducers should be tested with waveforms as close as possible to real working conditions. To assess the metrological characteristic of DC voltage and current transducers under real operating conditions, this paper presents a calibration set up able to generate up to 6 kV for DC voltage and up to 300 A for DC current. The system is able to generate complex and non-stationary test signals which go beyond the standard characterization procedures. Dynamic tests can be derived from real signals obtained from experimental data. For this aim, a specific software tool was developed and here it is presented

Personality traits related to problematic Facebook use

The American Psychiatric Association (APA) encouraged research in the area of Internet Gaming Disorder, by including it in the Conditions for Further Study section of the Diagnostic and Statistical Manual of Mental Disorders , 5th Edition (DSM-5; APA, 2013). The present study attempted to determine which personality traits were associated with problematic Facebook use, a subset of problematic Internet use. The Bergen Facebook Addiction Scale (BFAS), Narcissistic Personality Inventory-Sixteen (NPI-16), International Personality Item Pool (IPIP) items related to extraversion, IPIP items related to neuroticism, Internet Addiction Test (1AT), Facebook Intensity Scale (FBI), a demographic information form, and Exploratory Facebook Use Questionnaire were used to determine if specific personality traits were associated with problematic Facebook use. Participants were 295 Facebook users, recruited through social media. Participants reported more Facebook friends and the average participant age was over a decade older than in prior studies. The average number of hours spent on Facebook per day was similar to previous research. Females reported having significantly more Facebook friends and yielded significantly lower scores on personality measures than males. On the three measures of problematic Facebook use, results were mixed. Females produced lower scores than males on two measures and higher scores on a third measure. Additionally, results suggest narcissism, extraversion, and neuroticism predict problematic Facebook use in males, but not females. Higher levels of narcissism and extroversion were found to be associated with higher scores on measures of problematic Facebook use. Additionally, neuroticism and extraversion were significant positive predictors of problematic Facebook use. Positive endorsement of Exploratory Facebook Use Questions was associated with higher scores on two measures of problematic Facebook use. Lastly, participants with higher problematic Internet use also reported higher levels of problematic Facebook use. Continued research is needed to understand better the full nature of problematic Internet and/or subsets (i.e., problematic Facebook use)

Loss of epigenetic regulator TET2 and oncogenic KIT regulate myeloid cell transformation via PI3K pathway

Mutations in KIT and TET2 are associated with myeloid malignancies. We show that loss of TET2-induced PI3K activation and -increased proliferation is rescued by targeting the p110α/δ subunits of PI3K. RNA-Seq revealed a hyperactive c-Myc signature in Tet2-/- cells, which is normalized by inhibiting PI3K signaling. Loss of TET2 impairs the maturation of myeloid lineage-derived mast cells by dysregulating the expression of Mitf and Cebpa, which is restored by low-dose ascorbic acid and 5-azacytidine. Utilizing a mouse model in which the loss of TET2 precedes the expression of oncogenic Kit, similar to the human disease, results in the development of a non-mast cell lineage neoplasm (AHNMD), which is responsive to PI3K inhibition. Thus, therapeutic approaches involving hypomethylating agents, ascorbic acid, and isoform-specific PI3K inhibitors are likely to be useful for treating patients with TET2 and KIT mutations

Altered miR-193a-5p expression in children with cow's milk allergy

Cow's milk allergy (CMA) is one of the most common food allergies in children. Epigenetic mechanisms have been suggested to play a role in CMA pathogenesis. We shown that DNA methylation of Th1/Th2 cytokine genes and FoxP3 affects CMA disease course. Preliminary evidence suggest that also the miRNome could be implicated in the pathogenesis of allergy. Main study outcome was to comparatively evaluate miRNome in children with CMA and in healthy controls

Engineering The Unicellular Alga Phaeodactylum tricornutum For High-Value Plant Triterpenoid Production

Plant triterpenoids constitute a diverse class of organic compounds that play a major role in development, plant defense and environmental interaction. Several triterpenes have demonstrated potential as pharmaceuticals. One example is betulin, which has shown promise as a pharmaceutical precursor for the treatment of certain cancers and HIV. Major challenges for triterpenoid commercialization include their low production levels and their cost‐effective purification from the complex mixtures present in their natural hosts. Therefore, attempts to produce these compounds in industrially relevant microbial systems such as bacteria and yeasts have attracted great interest. Here we report the production of the triterpenes betulin and its precursor lupeol in the photosynthetic diatom Phaeodactylum tricornutum, a unicellular eukaryotic alga. This was achieved by introducing three plant enzymes in the microalga: a Lotus japonicus oxidosqualene cyclase and a Medicago truncatula cytochrome P450 along with its native reductase. The introduction of the L. japonicus oxidosqualene cyclase perturbed the mRNA expression levels of the native mevalonate and sterol biosynthesis pathway. The best performing strains were selected and grown in a 550L pilot scale photobioreactor facility. To our knowledge, this is the most extensive pathway engineering undertaken in a diatom and the first time that a sapogenin has been artificially produced in a microalga, demonstrating the feasibility of the photo‐bio‐production of more complex high‐value, metabolites in microalgae

Some Remarks on the Origin of Afro-Puerto Rican Spanish

A number of proposals have tried to account for the genesis and development of a set of Afro-Hispanic language varieties, the vernaculars ​​that formed in Latin America from the contact between African languages ​​and Spanish in colonial times (Sessarego 2021). This article presents a sociohistorical and linguistic analysis of Loza Spanish (LS), an Afro-Puerto Rican vernacular spoken in Loíza, Puerto Rico by the descendants of the Africans brought to this Caribbean island in colonial times to work as slaves on sugarcane plantations. This article assesses the evolution of this variety and its implications for creole studies. In so doing, it contributes to the long-lasting debate on the reasons behind the paucity of Spanish-based creoles in the Americas (Granda 1968 et seq.).Una serie de propuestas han tratado de dar cuenta de la génesis y desarrollo de un conjunto de variedades lingüísticas afrohispánicas, los vernáculos que se formaron en América Latina a partir del contacto de las lenguas africanas y el español en la época colonial (Sessarego 2021). Este artículo presenta un análisis sociohistórico y lingüístico del español de Loíza (EL), una variedad vernácula afropuertorriqueña hablada en Loíza, Puerto Rico, por los descendientes de los africanos traídos a esta isla caribeña en la época colonial para trabajar como esclavos en las plantaciones de caña de azúcar. Este artículo evalúa la evolución de esta variedad y sus implicaciones para los estudios de las lenguas criollas. Al hacerlo, contribuye al prolongado debate sobre las razones detrás de la escasez de variedades criollas de base española en América (Granda 1968 et seq.)