Bio-based ionic liquid crystal for stainless steel-sapphire high temperature ultralow friction

In the present work, the biobased protic ionic liquid crystal bis(2-hydroxyethyl) ammonium palmitate (DPA) has been studied as neat lubricant under linear reciprocating sliding at 75 °C, in the liquid crystalline region, and at 110 °C, above its melting point. Three different tribopairs have been studied using AISI 52100 steel, AISI 316L stainless steel and sapphire balls against AISI 316L disks. Tribological results at 75 °C are in agreement with the different sliding pairs and contact conditions. At 110 °C, a sharp friction coefficient reduction to reach an ultralow steady state value of 0.007–0.009, is observed for the sapphire-AISI 316L contact. Wear rate is also reduced in one order of magnitude. Results are related to water content in DPA, as determined by TG-MS. Wear mechanism are discussed upon the basis of optical and scanning electron microscopy (SEM/EDX) and of surface analysis by XPS.This research was funded by Spanish Ministerio de Ciencia e Innovación, Agencia Estatal de Investigación (AEI), and the European Union FEDER Program (Grant # MAT2017–85130-P). “Este trabajo es resultado de la actividad desarrollada en el marco del Programa de Ayudas a Grupos de Excelencia de la Región de Murcia, de la Fundación Seneca, Agencia de Ciencia y Tecnología de la Región de Murcia (Grant #19877/GERM/15)”

SARS-CoV-2 viral load in nasopharyngeal swabs is not an independent predictor of unfavorable outcome

The aim was to assess the ability of nasopharyngeal SARS-CoV-2 viral load at first patient’s hospital evaluation to predict unfavorable outcomes. We conducted a prospective cohort study including 321 adult patients with confirmed COVID-19 through RT-PCR in nasopharyngeal swabs. Quantitative Synthetic SARS-CoV-2 RNA cycle threshold values were used to calculate the viral load in log10 copies/mL. Disease severity at the end of follow up was categorized into mild, moderate, and severe. Primary endpoint was a composite of intensive care unit (ICU) admission and/or death (n = 85, 26.4%). Univariable and multivariable logistic regression analyses were performed. Nasopharyngeal SARS-CoV-2 viral load over the second quartile (≥ 7.35 log10 copies/mL, p = 0.003) and second tertile (≥ 8.27 log10 copies/mL, p = 0.01) were associated to unfavorable outcome in the unadjusted logistic regression analysis. However, in the final multivariable analysis, viral load was not independently associated with an unfavorable outcome. Five predictors were independently associated with increased odds of ICU admission and/or death: age ≥ 70 years, SpO2, neutrophils > 7.5 × 103/µL, lactate dehydrogenase ≥ 300 U/L, and C-reactive protein ≥ 100 mg/L. In summary, nasopharyngeal SARS-CoV-2 viral load on admission is generally high in patients with COVID-19, regardless of illness severity, but it cannot be used as an independent predictor of unfavorable clinical outcome

Dendritic cell deficiencies persist seven months after SARS-CoV-2 infection

Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV)-2 infection induces an exacerbated inflammation driven by innate immunity components. Dendritic cells (DCs) play a key role in the defense against viral infections, for instance plasmacytoid DCs (pDCs), have the capacity to produce vast amounts of interferon-alpha (IFN-α). In COVID-19 there is a deficit in DC numbers and IFN-α production, which has been associated with disease severity. In this work, we described that in addition to the DC deficiency, several DC activation and homing markers were altered in acute COVID-19 patients, which were associated with multiple inflammatory markers. Remarkably, previously hospitalized and nonhospitalized patients remained with decreased numbers of CD1c+ myeloid DCs and pDCs seven months after SARS-CoV-2 infection. Moreover, the expression of DC markers such as CD86 and CD4 were only restored in previously nonhospitalized patients, while no restoration of integrin β7 and indoleamine 2,3-dyoxigenase (IDO) levels were observed. These findings contribute to a better understanding of the immunological sequelae of COVID-19

The Physics of Star Cluster Formation and Evolution

© 2020 Springer-Verlag. The final publication is available at Springer via https://doi.org/10.1007/s11214-020-00689-4.Star clusters form in dense, hierarchically collapsing gas clouds. Bulk kinetic energy is transformed to turbulence with stars forming from cores fed by filaments. In the most compact regions, stellar feedback is least effective in removing the gas and stars may form very efficiently. These are also the regions where, in high-mass clusters, ejecta from some kind of high-mass stars are effectively captured during the formation phase of some of the low mass stars and effectively channeled into the latter to form multiple populations. Star formation epochs in star clusters are generally set by gas flows that determine the abundance of gas in the cluster. We argue that there is likely only one star formation epoch after which clusters remain essentially clear of gas by cluster winds. Collisional dynamics is important in this phase leading to core collapse, expansion and eventual dispersion of every cluster. We review recent developments in the field with a focus on theoretical work.Peer reviewe

Ionic Liquid Crystals in Tribology

The present work intends to provide a brief account of the most recent advances in the use of ionic liquid crystals (ILCs) in the field of tribology, that is, the development of new lubricants with the ability to reduce the coefficients of friction and the wear rates of materials under sliding conditions. After a definition of ILCs and their relationship with neutral liquid crystals (LCs) and ionic liquids (ILs), the review will be focused on the influence of molecular structure and composition on the tribological performance, the combination with base oils, surfactants or water, and the different sliding configuration and potential applications. The main mechanisms proposed in order to justify the lubricating ability of ILCs will be analyzed. Special emphasis will be made for recent results obtained for fatty acid derivatives due to their renewable and environmentally friendly nature

Entorno inflamatorio diferencial en pacientes con osteoporosis y diabetes mellitus tipo 2

Objetive: Type 2 diabetes mellitus (DM2) and osteoporosis are diseases associated with a pro‐inflammatory environment, the prevention of which through new therapeutic strategies could prevent their development. However, there are few studies that evaluate the inflammatory profile of osteoporosis in patients with DM2. This study focuses on evaluating the inflammatory immune response through serum concentrations of nine cytokines, two of them anti‐inflammatory (IL‐10, IL‐5) and six pro‐inflammatory (IL‐2, IL‐6, IL‐12 (p70), IL‐17A, TNFα and IFNγ) in 163 individuals with DM2 and 47 controls. A subpopulation, made up of 43 DM2 patients without osteoporosis, and 33 with osteoporosis, was analyzed in greater depth at the level of bone parameters. Furthermore, we have assessed the calciotropic hormones, bone remodeling markers, bone mineral density and vertebral fractures in the population, and we have analyzed the relationship of the cytokines tested with DM2, osteoporosis and prevalent vertebral fractures. Patients with DM2 had significantly higher serum concentrations of IL‐10 compared to the control group (0.5±1 vs. 0.14±0.3 pg/ml; p=0.016) and the levels of IL12 p70 were shown lower in patients with DM2 compared to controls (2.9±1.6 vs. 3.9±3.1 pg/ml; p=0.027). In the group of patients with DM2 and osteoporosis, the levels of the cytokine IL‐6 were elevated compared to the group with DM2 without osteoporosis (10.9±14.6 vs. 4.5±7.0; p=0.017). An association of IL‐5 was also observed, with its lowest levels in the DM2 group with osteoporosis (1.7±0.2 vs. 3.8±0.6; p=0.032). Furthermore, IL‐5 showed a direct correlation with the levels of the bone formation biomarker alkaline bone phosphatase (r=0.277, p=0.004) in the subpopulation of patients with DM2. The rest of cytokines did not show significant differences. In conclusion, our findings indicate that in our study population, patients with DM2 compared to healthy subjects present an inflammatory profile opposite to what is expected in a hyperglycemic situation, probably as a compensatory response to the inflammation caused. The cytokine profile is modified in the subpopulation of diabetic patients, depending on the presence of osteoporosis. In this case, the inflammatory profile in the presence of osteoporosis is consistent with the expected response.Este estudio ha sido financiado con las ayudas para realización de proyectos otorgadas por las fundaciones FEIOMM y SEEN, así como por el proyecto de la Consejería de Salud y familias PI-0450-2019. Además, el Dr. Jiménez-López agradece la financiación al programa de investigación Europeo Marie Curie (FP7--PEOPLE-2011-IOF, número de referencia PIOF-GA-2011-301550), así como al Ministerio de Economía, Industria y Competitividad por el proyecto del programa Ramón y Cajal (RYC-2014-16536) y el proyecto BFU2016-77243-P

Manejo nutricional de la esclerosis lateral amiotrófica: resumen de recomendaciones

La esclerosis lateral amiotrófica (ELA) es una enfermedad neurodegenerativa que se caracteriza por debilidad muscular y discapacidad progresivas que acaban produciendo fallo respiratorio y disfagia que conducen a la muerte. El término surge de la combinación de los hallazgos clínicos, caracterizados por la atrofia muscular (amiotrofia), y los hallazgos anatomopatológicos con gliosis y esclerosis del área dorsolateral de la médula espinal, entre otros (1). La ELA es la enfermedad más común de las enfermedades de la motoneurona. Su incidencia global es de 1,5 a 2,7 nuevos casos/100.000 habitantes/año, con una prevalencia media de 2,7 a 7,4 casos/100.000 habitantes (2). En España, según la Sociedad Española de Neurología, se diagnostican tres nuevos casos cada día, lo que supone una incidencia anual de 1/100.000 habitantes y una prevalencia de 3,5/100.000 (3)