Search results for "Node"

Acoustical properties of air-saturated porous material with periodically distributed dead-end pores

2015

International audience; A theoretical and numerical study of the sound propagation in air-saturated porous media with straight main pores bearing lateral cavities (dead-ends) is presented. The lateral cavities are located at " nodes " periodically spaced along each main pore. The effect of periodicity in the distribution of the lateral cavities is studied, and the low frequency limit valid for the closely spaced dead-ends is considered separately. It is shown that the absorption coefficient and transmission loss are influenced by the viscous and thermal losses in the main pores as well as their perforation rate. The presence of long or short dead-ends significantly alters the acoustical pro…

Could the acid-base status of Antarctic sea urchins indicate a better-than-expected resilience to near-future ocean acidification?

2015

13 pages; International audience; Increasing atmospheric carbon dioxide concentration alters the chemistry of the oceans towards more acidic conditions. Polar oceans are particularly affected due to their low temperature, low carbonate content and mixing patterns, for instance upwellings. Calcifying organisms are expected to be highly impacted by the decrease in the oceans' pH and carbonate ions concentration. In particular, sea urchins, members of the phylum Echinodermata, are hypothesized to be at risk due to their high-magnesium calcite skeleton. However, tolerance to ocean acidification in metazoans is first linked to acid–base regulation capacities of the extracellular fluids. No infor…

Pamati atbrīvošanai no valsts nodevas un drošības naudas samaksas administratīvajā tiesā

2020

Maģistra darba pētījuma objekts ir pamati atbrīvošanai no valsts nodevas un drošības naudas samaksas administratīvajā tiesā. Darba struktūra ir veidota, apskatot valsts nodevas un drošības naudas jēdzienu, regulējumu Latvijā un ārvalstīs, kā arī darbā aplūkota un aktualizēta tiesu prakse jautājumā par atbrīvošanu no valsts nodevas un drošības naudas. Maģistra darbā izdarīti secinājumi par tiesu praksē konstatētajām problēmām atbrīvojot personas no valsts nodevas un drošības naudas samaksas, kā arī izteikti priekšlikumi grozījumiem Administratīvā procesa likumā konstatēto trūkumu un problēmu risināšanai.

Durability of Dolutegravir-Based Regimens: A 5-Year Prospective Observational Study

2021

This study evaluates the frequency and causes of dolutegravir (DTG) discontinuation along 5 years of follow-up, in both antiretroviral treatment (ART)-naive and experienced people living with HIV (PLWH). This is a prospective multi-center cohort study enrolling PLWH on DTG from July 2014 until November 2020. DTG-durability was investigated using the Kaplan-Meier survival curve. The Cox proportional-hazards model was used for estimating the hazard ratio (HR) of DTG discontinuation for any cause, and for adverse events (AEs). Nine hundred sixty-three PLWH were included, 25.3% were women and 28.0% were ART-naive. Discontinuations for any causes were 10.1 [95% confidence interval (95% CI) 8.9-1…

Sentinel Lymph Node in Aged Endometrial Cancer Patients “The SAGE Study”: A Multicenter Experience

2021

ObjectiveThe incidence of endometrial cancer is increasing in elderly people. Considering that aging progressively affects lymphatic draining function, we aimed to define its impact on IGC uptake during SLN mapping.MethodsA multicenter retrospective cohort of endometrial cancer patients with apparently early-stage endometrial cancer undergoing complete surgical staging with SLN dissection was identified in four referral cancer centers from May 2015 to March 2021. Patients were classified in Group 1 (<65 years old) and Group 2 (≥65 years old). The primary endpoint was the assessment of the overall, bilateral, and unsuccessful SLN mapping in the two groups. Secondary outcomes were the …

Intraflagellar transport protein 172 is essential for primary cilia formation and plays a vital role in patterning the mammalian brain

2008

AbstractIFT172, also known as Selective Lim-domain Binding protein (SLB), is a component of the intraflagellar transport (IFT) complex. In order to evaluate the biological role of the Ift172 gene, we generated a loss-of-function mutation in the mouse. The resulting Slb mutant embryos die between E12.5 and 13.0, and exhibit severe cranio-facial malformations, failure to close the cranial neural tube, holoprosencephaly, heart edema and extensive hemorrhages. Cilia outgrowth in cells of the neuroepithelium is initiated but the axonemes are severely truncated and do not contain visible microtubules. Morphological and molecular analyses revealed a global brain-patterning defect along the dorsal–…

Catalytic and Electrical Properties of La1-xSrxCr1-yFeyO3-d as anodes for IT-SOFCs

2014

Description of Solid-to-Solid Redox Processes Based on the Voltammetry of Immobilized Particles Methodology: A Logistic Approximation

2022

A semiempirical model to describe the voltammetry of nontopotactic solid-to-solid redox processes occurring in the voltammetry of immobilized particles (VIMP) electrochemistry is described. It is applied to the reduction of solid metal compounds to the corresponding metal in contact with suitable electrolytes. The model is based on the assumption that the transferred charge is a logistic function of the applied potential, a situation that applies for reversible redox processes involving strongly adsorbed reactants. The model satisfactorily applies to reproduce linear potential scan curves recorded for graphite electrodes modified with different lead compounds (PbO, PbCl2·2H2O, lead-tin yell…

Lithium adsorption at prismatic graphite surfaces enhances interlayer cohesion

2013

Abstract We use density functional calculations to determine the binding sites and binding energies of Li + at graphene edges and prismatic graphite surfaces. Binding is favorable at bare and carbonyl terminated surfaces, but not favorable at hydrogen terminated surfaces. These findings have implications for the exfoliation of graphitic anodes in lithium-ion batteries that happens if solute and solvent co-intercalate. First, specific adsorption facilitates desolvation of Li + . Second, chemisorption lowers the surface energy by about 1 J m −2 prismatic surface area, and gives graphite additional stability against exfoliation. The results offer an explanation for experiments that consistentl…

Studio di materiali avanzati per celle a combustibile ad ossidi solidi: influenza dei droganti e delle tecniche di sintesi sulle proprietà di anodi e…

2014

Today fuel cell (FC) technology is envisaged as a strategic alternative for providing clean energy through the exploitation of renewable sources; FC research is substantially funded by governments as a mean to meet the global market demand of zero environmental impact. Due to the high level of efficiency, FC devices are already able to compete with the existing power generation technologies and, in particular, solid oxide fuel cells (SOFCs) plants for stationary application constitute one the most efficient way to produce electric power and heat. Nowadays, the main challenges for SOFC research activity are: i) improving costs and durability, by reducing the operating temperature from ∼1000°…