Dimension and support of underground slate mines

[Abstract] We've studied the conditions about dimensions and support ofan underground mine of roofing slate in Galice, worked by rooms with continuous pillars. The rock mass was characterized by the empiric and analitic methods, calculating the stable pillar wide along the mine by the theory of attributed area and by a model of finite elements, where the breaking criterion ofHoek and Brown was applied. The result was a parabolic relationship between pillar wide and mine length. Stability studies in an isolated stope give an elastic performance on the periphery of the room, without tractions. Although the stability ofthe mine is good, a systematic support is recommended on the basis of bolts, that will be reinforced with projected concret at the top, and a singular treatment of the detected wedges

Enabling propagation of anisotropic polaritons along forbidden directions via a topological transition

Polaritons with directional in-plane propagation and ultralow losses in van der Waals (vdW) crystals promise unprecedented manipulation of light at the nanoscale. However, these polaritons present a crucial limitation: their directional propagation is intrinsically determined by the crystal structure of the host material, imposing forbidden directions of propagation. Here, we demonstrate that directional polaritons (in-plane hyperbolic phonon polaritons) in a vdW crystal (α-phase molybdenum trioxide) can be directed along forbidden directions by inducing an optical topological transition, which emerges when the slab is placed on a substrate with a given negative permittivity (4H–silicon carbide). By visualizing the transition in real space, we observe exotic polaritonic states between mutually orthogonal hyperbolic regimes, which unveil the topological origin of the transition: a gap opening in the dispersion. This work provides insights into optical topological transitions in vdW crystals, which introduce a route to direct light at the nanoscale

Experiencia inicial con la prótesis de despliegue rápido en posición aórtica Edwards Intuity

ResumenObjetivoDisponemos de una nueva clase de prótesis aórticas de despliegue rápido para tratamiento quirúrgico de la estenosis aórtica. Permitirían disminuir los tiempos quirúrgicos y facilitarían la cirugía mínimamente invasiva. Presentamos nuestra experiencia inicial con la válvula Edwards Intuity en el contexto del estudio multicéntrico Foundation.Pacientes y métodosEntre septiembre de 2012 y febrero de 2014 se implantaron 25 prótesis aórticas Edwards Intuity en 26 pacientes (77±4,3años; 52% varones). Veinticuatro (96%) fueron reemplazo valvular aislado, y 9 pacientes (36%) tuvieron abordaje mínimamente invasivo. Los pacientes fueron estudiados al alta, a los 3meses y al año de la intervención.ResultadosHubo éxito en el implante en el 96,2% de los pacientes (25/26). No hubo mortalidad hospitalaria. Seguimiento medio de 11±5,4meses, supervivencia acumulada del 96%. Un paciente falleció a los 11meses por un ictus isquémico. El tiempo medio de pinzamiento aórtico fue de 38,2±10,1min y el tiempo medio de circulación extracorpórea, de 62,4±11,1min. A los 3meses, el área valvular efectiva media fue de 1,70±0,42cm2. El 91% de los pacientes (23/25) estaban en grado funcionali en el seguimiento.ConclusionesEl implante de la válvula Edwards Intuity para el tratamiento de la estenosis aórtica ha sido factible, seguro y eficaz. Los tiempos de isquemia miocárdica y de circulación extracorpórea parecen reducirse en comparación con la cirugía valvular aórtica habitual. El comportamiento hemodinámico inicial de la prótesis Edwards Intuity es excelente.AbstractObjectiveA new class of rapid deployment prostheses is now available for surgical treatment of aortic stenosis. These prostheses offer the possibility of reducing the duration of cardiopulmonary bypass and aortic clamping times, and facilitate the use of minimally invasive surgery. We present our initial experience with the Edwards Intuity valve in the context of a multicentre Foundation study.Patients and methodsBetween September 2012 and February 2014, 25 Edwards Intuity valves were implanted in 26 patients (77±4.3years; 52% male). Twenty-four (96%) were isolated aortic valve replacement; a minimally invasive approach was used on 9 patients (36%). Patients were studied at discharge, three months, and one year after surgery.ResultsImplantation success rate was 96.2% (25/26). There was no hospital mortality. Mean follow-up of 11±5.54months, cumulative survival of 96%. One patient died eleven months after surgery due to ischaemic stroke. The mean aortic clamping time was 38.2±10.1minutes, and the mean cardiopulmonary bypass (CPB) time was 62.4±11.1minutes. In the echocardiography at 3months, the mean effective valve area was 1.70±0.42cm2, and 91% of patients (23/25) were in functional classi NYHA at follow-up.ConclusionsThe implantation of the Edwards Intuity valve for surgical treatment of aortic stenosis has shown to be feasible, safe and effective. Times of myocardial ischaemia and extracorporeal circulation appear to be reduced compared with normal aortic valve surgery. The initial haemodynamic performance of the Edwards Intuity prosthesis is excellent

Planar refraction and lensing of highly confined polaritons in anisotropic media

Refraction between isotropic media is characterized by light bending towards the normal to the boundary when passing from a low- to a high-refractive-index medium. However, refraction between anisotropic media is a more exotic phenomenon which remains barely investigated, particularly at the nanoscale. Here, we visualize and comprehensively study the general case of refraction of electromagnetic waves between two strongly anisotropic (hyperbolic) media, and we do it with the use of nanoscale-confined polaritons in a natural medium: alpha-MoO3. The refracted polaritons exhibit non-intuitive directions of propagation as they traverse planar nanoprisms, enabling to unveil an exotic optical effect: bending-free refraction. Furthermore, we develop an in-plane refractive hyperlens, yielding foci as small as lambdap/6, being lambdap the polariton wavelength (lambda0/50 compared to the wavelength of free-space light). Our results set the grounds for planar nano-optics in strongly anisotropic media, with potential for effective control of the flow of energy at the nanoscale.G.Á.-P. and J.T.-G. acknowledge support through the Severo Ochoa Program from the Government of the Principality of Asturias (nos. PA-20-PF-BP19-053 and PA-18-PF-BP17-126, respectively). S.X. acknowledges the support from Independent Research Fund Denmark (Project No. 9041-00333B). B.C. acknowledges the support from VILLUM FONDEN (No. 00027987). The Center for Nanostructured Graphene is sponsored by the Danish National Research Foundation (Project No. DNRF103.) K.V.V. and V.S.V. gratefully acknowledge the financial support from the Ministry of Science and Higher Education of the Russian Federation (Agreement No. 075-15-2021-606). J.M.-S. acknowledges financial support through the Ramón y Cajal Program from the Government of Spain (RYC2018-026196-I). A.Y.N. and J.I.M. acknowledge the Spanish Ministry of Science, Innovation and Universities (national projects MAT201788358-C3-3-R and PID2019-104604RB/AEI/10.13039/501100011033). R.H. acknowledges financial support from the Spanish Ministry of Science, Innovation and Universities (national project RTI2018-094830-B-100 and the project MDM-2016-0618 of the Marie de Maeztu Units of Excellence Program) and the Basque Government (grant No. IT1164-19). A.Y.N. also acknowledges the Basque Department of Education (grant no. PIBA-2020-1-0014). P.A.-G. acknowledges support from the European Research Council under starting grant no. 715496, 2DNANOPTICA and the Spanish Ministry of Science and Innovation (State Plan for Scientific and Technical Research and Innovation grant number PID2019-111156GB-I00)

Active and Passive Tuning of Ultranarrow Resonances in Polaritonic Nanoantennas

[EN] Optical nanoantennas are of great importance for photonic devices and spectroscopy due to their capability of squeezing light at the nanoscale and enhancing light-matter interactions. Among them, nanoantennas made of polar crystals supporting phonon polaritons (phononic nanoantennas) exhibit the highest quality factors. This is due to the low optical losses inherent in these materials, which, however, hinder the spectral tuning of the nanoantennas due to their dielectric nature. Here, active and passive tuning of ultranarrow resonances in phononic nanoantennas is realized over a wide spectral range (approximate to 35 cm(-1), being the resonance linewidth approximate to 9 cm(-1)), monitored by near-field nanoscopy. To do that, the local environment of a single nanoantenna made of hexagonal boron nitride is modified by placing it on different polar substrates, such as quartz and 4H-silicon carbide, or covering it with layers of a high-refractive-index van der Waals crystal (WSe2). Importantly, active tuning of the nanoantenna polaritonic resonances is demonstrated by placing it on top of a gated graphene monolayer in which the Fermi energy is varied. This work presents the realization of tunable polaritonic nanoantennas with ultranarrow resonances, which can find applications in active nanooptics and (bio)sensing.J.M.-S. acknowledges financial support from the Ramon y Cajal Program of the Government of Spain and FSE (Grant No. RYC2018-026196-I) and the Spanish Ministry of Science and Innovation (State Plan for Scientific and Technical Research and Innovation Grant Number PID2019-110308GA-I00). P.A.-G. acknowledges support from the European Research Council under starting Grant No. 715496, 2DNANOPTICA, and the Spanish Ministry of Science and Innovation (State Plan for Scientific and Technical Research and Innovation Grant Number PID2019-111156GB-I00). G.a.-P. and J.T.-G. acknowledge support through the Severo Ochoa Program from the Government of the Principality of Asturias (Grant nos. PA20-PF-BP19-053 and PA-18-PF-BP17-126, respectively). A.Y.N. acknowledges the Spanish Ministry of Science and Innovation (Grant Nos. MAT201788358-C3-3-R and PID2020-115221GB-C42) and the Basque Department of Education (Grant No. PIBA-2020-1-0014) J.H.E. acknowledges support for h-BN crystal growth from the National Science Foundation, Award Number CMMI-1538127. R.H. acknowledges financial support from the Spanish Ministry of Science, Innovation and Universities (National Project Grant No. RTI2018-094830-B-100 and the Project Grant No. MDM-2016-0618 of the Marie de Maeztu Units of Excellence Program), the Basque Government (Grant No. IT1164-19), and the European Union's Horizon 2020 research and innovation programme under the Graphene Flagship (Grant Agreement Numbers 785219 and 881603, GrapheneCore2 and GrapheneCore3). I.D. acknowledges the Basque Government (Grant No. PRE_2019_2_0164). Work at MIT was partly supported through AFOSR Grant No. FA9550-16-1-0382, through the NSF QII-TAQS program (Grant No. 1936263), and the Gordon and Betty Moore Foundation EPiQS Initiative through Grant No. GBMF9643 to P.J.-H

Cannabinoid receptor CB2 drives HER2 pro-oncogenic signaling in breast cancer

Pharmacological activation of cannabinoid receptors elicits antitumoral responses in different models of cancer. However, the biological role of these receptors in tumor physio-pathology is still unknown. We analyzed CB2 cannabinoid receptor protein expression in two series of 166 and 483 breast tumor samples operated in the University Hospitals of Kiel, Tübingen and Freiburg between 1997 and 2010. CB2 mRNA expression was also analyzed in previously published DNA microarray datasets. The role of CB2 in oncogenesis was studied by generating a mouse line that expresses the HER2 rat ortholog (neu) and lacks CB2, and by a variety of biochemical and cell biology approaches in human breast cancer cells in culture and in vivo, upon modulation of CB2 expression by si/shRNAs and overexpression plasmids. CB2-HER2 molecular interaction was studied by co-localization, coimmunoprecipitation and proximity ligation assays. We show an association between elevated CB2 expression in HER2+ breast tumors and poor patient prognosis. We also demonstrate that genetic inactivation of CB2 impairs tumor generation and progression in MMTV-neu mice. Moreover, we show that HER2 upregulates CB2 expression by activating the transcription factor ELK1 via the ERK cascade, and that an increased CB2 expression activates the HER2 prooncogenic signaling machinery at the level of the tyrosine kinase c-SRC. Finally, HER2 and CB2 form heteromers in cancer cells. Our findings reveal an unprecedented role of CB2 as a pivotal regulator of HER2 pro-oncogenic signaling in breast cancer, and suggest that CB2 may be a biomarker with prognostic value in these tumors

Nanoscale-confined Terahertz Polaritons in a van der Waals Crystal

Electromagnetic field confinement is crucial for nanophotonic technologies, since it allows for enhancing light-matter interactions, thus enabling light manipulation in deep sub-wavelength scales. In the terahertz (THz) spectral range, radiation confinement is conventionally achieved with specially designed metallic structures - such as antennas or nanoslits - with large footprints due to the rather long wavelengths of THz radiation. In this context, phonon polaritons - light coupled to lattice vibrations - in van der Waals (vdW) crystals have emerged as a promising solution for controlling light beyond the diffraction limit, as they feature extreme field confinements and low optical losses. However, experimental demonstration of nanoscale-confined phonon polaritons at THz frequencies has so far remained elusive. Here, we provide it by employing scattering-type scanning near-field optical microscopy (s-SNOM) combined with a free-electron laser (FEL) to reveal a range of low-loss polaritonic excitations at frequencies from 8 to 12 THz in the vdW semiconductor ${\alpha}-MoO_3$. We visualize THz polaritons with i) in-plane hyperbolic dispersion, ii) extreme nanoscale field confinement (below ${\lambda}_o/75$) and iii) long polariton lifetimes, with a lower limit of > 2 ps

TP97 299. Experiencia en el uso de válvula aórtica biológica freedom solo en endocarditis

IntroducciónLas válvulas aórticas biológicas sin soporte Sorin Freedom Solo (FS) han demostrado una mejoría en el aumento del orificio de área efectivo, así como un mejor perfil en los gradientes transvalvulares, fracción de eyección del ventrículo izquierdo (FEVI) y regresión de la hipertrofia ventricular izquierda. También, se ha comprobado una reducción en los tiempos de isquemia miocárdica y de circulación extracorpórea. Sin embargo no hay mucha información sobre su comportamiento en el contexto de endocarditis valvular.Material y métodosDesde noviembre de 2006 – septiembre 2011, se implantaron 17 prótesis FS en 16 pacientes (50% hombres, 60,2±15 años) por endocarditis bacteriana. Se determinó la cantidad de plaquetas en el día 5 postimplante, así como la fracción de eyección (FE) y los gradientes transvalvulares posquirúrgicos. Seguimiento medio de 22,5±26 meses.ResultadosLa prevalencia de trombocitopenia (< 150.000 plaquetas) y trombocitopenia grave (< 50.000 plaquetas) ha sido de 68,8 y 31,3%, respectivamente. Hubo un total de 4 muertes hospitalarias (25%), 2 intraoperatorias. Gradiente transvalvular medio de 22±18mmHg, FEVI postoperatoria media de 52,4±10,3%. Tres pacientes fueron reintervenidos, 2 por deterioro precoz (16%), 1 por nueva endocarditis (8%).ConclusiónLa prótesis aórtica biológica sin soporte FS muestra un buen perfil hemodinámico, mejorando significati-vamente los gradientes transvalvulares.Nuestra prevalencia de trombocitopenia al quinto día y durabilidad de la válvula se encuentran en valores similares a lo publicado en la literatura.El uso de dicha prótesis en endocarditis aórtica debe considerarse una alternativa eficaz al demostrarse baja tasa de reincidencia de endocarditis

Vitamin D Status in Hospitalized Patients with SARS-CoV-2 Infection

Background: The role of vitamin D status in COVID-19 patients is a matter of debate. Objectives: To assess serum 25-hydroxyvitamin D (25OHD) levels in hospitalized patients with COVID-19 and to analyze the possible influence of vitamin D status on disease severity. Methods: Retrospective case-control study of 216 COVID-19 patients and 197 population-based controls. Serum 25OHD levels were measured in both groups. The association of serum 25OHD levels with COVID-19 severity (admission to the intensive care unit, requirements for mechanical ventilation, or mortality) was also evaluated. Results: Of the 216 patients, 19 were on vitamin D supplements and were analyzed separately. In COVID-19 patients, mean ± standard deviation 25OHD levels were 13.8 ± 7.2 ng/mL, compared with 20.9 ± 7.4 ng/mL in controls (P < .0001). 25OHD values were lower in men than in women. Vitamin D deficiency was found in 82.2% of COVID-19 cases and 47.2% of population-based controls (P < .0001). 25OHD inversely correlates with serum ferritin (P = .013) and D-dimer levels (P = .027). Vitamin D-deficient COVID-19 patients had a greater prevalence of hypertension and cardiovascular diseases, raised serum ferritin and troponin levels, as well as a longer length of hospital stay than those with serum 25OHD levels ?20 ng/mL. No causal relationship was found between vitamin D deficiency and COVID-19 severity as a combined endpoint or as its separate components. Conclusions: 25OHD levels are lower in hospitalized COVID-19 patients than in population-based controls and these patients had a higher prevalence of deficiency. We did not find any relationship between vitamin D concentrations or vitamin deficiency and the severity of the disease.The Camargo Cohort Study was supported by grants from the Instituto de Salud Carlos III (PI18/00762), Ministerio de Economía y Competitividad, Spain, which included FEDER funds from the EU