233 research outputs found
A fractional porous medium equation
We develop a theory of existence, uniqueness and regularity for a porous
medium equation with fractional diffusion, in , with ,
and . An -contraction semigroup is
constructed and the continuous dependence on data and exponent is established.
Nonnegative solutions are proved to be continuous and strictly positive for all
,
El seguro social en Iberoamérica
Esta obra se a valido preferentemente de la legislaciĂłn positiva de las repĂșblicas hispano-lucitanas, que en su variedad, hermandad y progreso de hoy dan un valor y una facilidad del todo insuperables en la comparaciĂłn de sus individualidades, traspasando los mares tan solo cuando el autor a tenido que buscar el origen y la particularidad de un sistema o hecho
Fast Hardware Implementations of Static P Systems
In this article we present a simulator of non-deterministic static P systems using Field Programmable Gate Array (FPGA) technology. Its major feature is a high performance, achieving a constant processing time for each transition. Our approach is based on representing all possible applications as words of some regular context-free language. Then, using formal power series it is possible to obtain the number of possibilities and select one of them following a uniform distribution, in a fair and non-deterministic way. According to these ideas, we yield an implementation whose results show an important speed-up, with a strong independence from the size of the P system
NANoREG harmonised terminology for environmental health and safety assessment of nanomaterials
Several terms in the field of environmental health and safety (EHS) assessment of chemicals and nanomaterials (hereinafter NMs) have been defined or used by the scientific community and different organisations, including international bodies, European authorities, and industry associations. This is also true for multidisciplinary projects such as NANoREG, which aims at supporting regulatory authorities and industry in dealing with EHS issues of manufactured NMs.
The objective of the present JRC technical report is to publish the harmonised terminology that has been developed and used within NANoREG. It has been agreed upon and adopted by all project partners in their activities and related documents. The report specifically includes: i) the methodology used to select key terms that form the harmonised terminology and to develop harmonised definitions; ii) the existing literature definitions that have been used as a starting point to develop for each key term a harmonised definition; and iii) the reason(s) behind the choices that have been made in drafting a definition. As far as possible, the harmonised definition is reproducing (an) already existing definition text(s), thus avoiding the creation of new and unwelcome information.
The discussion on the key terms to be considered for the harmonised terminology led to the selection of 43 key terms. The list includes terms with international regulatory relevance, such as those defined at OECD level, as well as terms that have a specific meaning and use under REACH.
The 'NANoREG Harmonised Terminology' has already proven very useful in the context of the OECD work, as support document to the April 2016 OECD Expert Meeting on 'Grouping and read-across for the hazard assessment of manufactured nanomaterials', and in a regulatory context, as support document to the work recently released by RIVM, ECHA and JRC on using (eco)toxicological data for bridging data gaps between nanoforms of the same substance (March 2016).
For quick access, the 'NANoREG Harmonised Terminology' is reported in Section 3.JRC.I.4-Nanobioscience
Esophageal Stenting in the Setting of Malignancy
Esophageal cancer is often diagnosed at an advanced stage, with many patients
found to have locoregional or metastatic disease at time of diagnosis. Because
of this, cure may be unlikely, leading treatment efforts to focus more on
symptom palliation and improving patient quality of life. The majority of
patients with advanced disease suffer from some degree of dysphagia. Palliative
efforts are therefore directed at relieving dysphagia, allowing patients to
manage their oropharyngeal secretions, reduce aspiration risk, and maintain
caloric intake orally. A variety of endoscopic treatment modalities have been
utilized with these objectives in mind, with options determined by the location
and size of the tumor, as well as the patient's expected prognosis. In this
article, we review the use of endoscopically-placed stents for palliation in
patients with advanced esophageal cancer. We discuss the history of stent use in
such cases, as well as more recent developments in stent technology. We give an
overview of some of the more commonly used stents in practice, discuss the
technique of insertion, and survey the short- and long-term outcomes of stent
placement
Biomechanical Test of a New Endoprosthesis for Cylindrical Medullary Canals in Dogs
Exo-endoprosthesis is a limb salvage procedure for animals, although only expensive metal devices have been described. Now-a-days, new materials for this type of implant could be considered due to novel and affordable manufacturing techniques. However, a factor of safety (FoS) should be considered. There are kinetic and kinematic studies of canine natural gaits, which can be used to establish an FoS for mechanical tests for new non-metallic devices. Polyetheretherketone (PEEK) is used in different specialties in human medicine. Its mechanical properties (and its close mechanical stiffness to that of bone) make this polymer an alternative to metals in veterinary traumatology. PEEK could also be used in 3D printing. The suitability of a novel inner part of an exo-endoprosthesis manufactured by fuse deposition modeling (FDM) was presented in this study for long canine bones. Mechanical characterization of 3D-printed PEEK material and ex vivo mechanical tests of a customized endoprosthesis were performed to address it. Young's modulus of 3D-printed PEEK suffered a reduction of 30% in relation to bulk PEEK. Customized 3D-printed PEEK endoprostheses had promising outcomes for the tibiae of 20 kg dogs. Pure compression tests of the non-inserted endoprostheses showed a maximum force of 936 +/- 199 N. In the bending tests of non-inserted endoprostheses, the PEEK part remained intact. Quasistatic mechanical tests of bone-inserted endoprostheses (compression-bending and pure compression tests) reached a maximum force of 785 +/- 101 N and 1,642 +/- 447 N, respectively. In fatigue tests, the samples reached 500,000 cycles without failure or detriment to their quasistatic results. These outcomes surpass the natural weight-bearing of dogs, even during a galloping pace. In conclusion, the 3D-printed PEEK part of the endoprosthesis for an exo-endoprosthesis can withstand loading, even during a galloping pace.Depto. de Medicina y CirugĂa AnimalFac. de VeterinariaTRUEComunidad de Madridpu
The prognostic impact of SIGLEC5-induced impairment of CD8+ T cell activation in sepsis
Immune checkpoint; Sepsis; T-cell exhaustionPunto de control inmunológico; Septicemia; Agotamiento de células TPunt de control immunitari; SÚpsia; Esgotament de cÚl·lules TBackground
Sepsis is associated with T-cell exhaustion, which significantly reduces patient outcomes. Therefore, targeting of immune checkpoints (ICs) is deemed necessary for effective sepsis management. Here, we evaluated the role of SIGLEC5 as an IC ligand and explored its potential as a biomarker for sepsis.
Methods
In vitro and in vivo assays were conducted to both analyse SIGLEC5's role as an IC ligand, as well as assess its impact on survival in sepsis. A multicentre prospective cohort study was conducted to evaluate the plasmatic soluble SIGLEC5 (sSIGLEC5) as a mortality predictor in the first 60 days after admission in sepsis patients. Recruitment included sepsis patients (n = 346), controls with systemic inflammatory response syndrome (n = 80), aneurism (n = 11), stroke (n = 16), and healthy volunteers (HVs, n = 100).
Findings
SIGLEC5 expression on monocytes was increased by HIF1α and was higher in septic patients than in healthy volunteers after ex vivo LPS challenge. Furthermore, SIGLEC5-PSGL1 interaction inhibited CD8+ T-cell proliferation. Administration of sSIGLEC5r (0.8 mg/kg) had adverse effects in mouse endotoxemia models. Additionally, plasma sSIGLEC5 levels of septic patients were higher than HVs and ROC analysis revealed it as a mortality marker with an AUC of 0.713 (95% CI, 0.656â0.769; p < 0.0001). KaplanâMeier survival curve showed a significant decrease in survival above the calculated cut-off (HR of 3.418, 95% CI, 2.380â4.907, p < 0.0001 by log-rank test) estimated by Youden Index (523.6 ng/mL).
Interpretation
SIGLEC5 displays the hallmarks of an IC ligand, and plasma levels of sSIGLEC5 have been linked with increased mortality in septic patients.This work was supported by grants from Instituto de Salud Carlos III (ISCIII) and âFondos FEDERâ to ELC (PIE15/00065, PI18/00148, PI14/01234, PI21/00869), to PP (20859/PI/18) and to CdF (PI21/01178), and received funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowaska-Curie grant agreement to KMH (No. 713673; âlaCaixaâ). R.L.-R. was supported by âPredoctotales de formaciĂłn en InvestigaciĂłnâ (PFIS) grant FI19/00334 and J.A.-O. by Sara Borrell grant CD21/00059 from ISCIII. The Vall d'Hebron University Hospital and Vall dâHebron Research Institute were supported by Plan Nacional de I+D+i 2013â2016, the ISCIII and Spanish Network for Research in Infectious Diseases (REIPI RD16/0016/0003)âco-financed by European Development Regional Fund âA way to achieve Europeâ, and by the European Unionâs Horizon 2020 Research and Innovation Program (JCRR, RF, JJGL, AF). Authors thank Emilio Llanos for his technical assistance
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