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PURPOSE: Demographic change will lead to an increase in age-associated cancers. The demand for primary treatment, especially oncologic therapies, is difficult to predict. This work is an attempt to project the demand for radiation therapy (RT) in 2030, taking into account demographic changes using prostate cancer (PC) as an example. MATERIALS AND METHODS: Using the GENESIS database of the Federal Statistical Office, we retrieved demographic population projections for 2030 and retrospective demographic surveys from 1999 to 2019. Additionally, we queried incidence rates for PC in the respective age groups of 50-54, 55-59, 60-64, 65-69, 70-74, 75-79, 80-84, and +85 years from 1999-2019 via the Federal Cancer Registry of the Robert Koch Institute. We used a regression method to determine the age-dependent correlation between the incidence of PC and the population size of the respective age group by combining the data from 1999 to 2019. This information was used to calculate the incidence rates in the age groups of the expected population for 2030 and the expected new cases of PC in 2030. Finally, we extrapolated the indications for the demand for RT based on data from the Report on Cancer Incidence in Germany from 2016. RESULTS: Considering a population-dependent incidence rate, an increase in new cases of PC is expected. This increase is particularly evident in the age groups of 70-74 and 80-84 years. With regards to RT, the estimate indicates an overall increase of 27.4% in demand. There is also a shift in RT demands towards older patients, especially in the 80- to 84-year-old age group. CONCLUSION: We observe an age-associated increase in primary cases of PC. This is likely to result in an increased demand for RT. The exact demand cannot be predicted. However, trends can be estimated to plan for the demand. This, though, requires a good database from cancer registries.
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CHESS, chopper spectrometer examining small samples, is a planned direct geometry neutron chopper spectrometer designed to detect and analyze weak signals intrinsic to small cross sections (e.g., small mass, small magnetic moments, or neutron absorbing materials) in powders, liquids, and crystals. CHESS is optimized to enable transformative investigations of quantum materials, spin liquids, thermoelectrics, battery materials, and liquids. The broad dynamic range of the instrument is also well suited to study relaxation processes and excitations in soft and biological matter. The 15 Hz repetition rate of the Second Target Station at the Spallation Neutron Source enables the use of multiple incident energies within a single source pulse, greatly expanding the information gained in a single measurement. Furthermore, the high flux grants an enhanced capability for polarization analysis. This enables the separation of nuclear from magnetic scattering or coherent from incoherent scattering in hydrogenous materials over a large range of energy and momentum transfer. This paper presents optimizations and technical solutions to address the key requirements envisioned in the science case and the anticipated uses of this instrument.
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PURPOSE: A clinical implementation of ion-beam radiography (iRad) is envisaged to provide a method for on-couch verification of ion-beam treatment plans. The aim of this work is to introduce and evaluate a method for quantitative water-equivalent thickness (WET) measurements for a specific helium-ion imaging system for WETs that are relevant for imaging thicker body parts in the future. METHODS: Helium-beam radiographs (αRads) are measured at the Heidelberg Ion-beam Therapy Center with an initial beam energy of 239.5 MeV/u. An imaging system based on three pairs of thin silicon pixel detectors is used for ion path reconstruction and measuring the energy deposition (dE) of each particle behind the object to be imaged. The dE behind homogeneous plastic blocks is related to their well-known WETs between 280.6 and 312.6 mm with a calibration curve that is created by a fit to measured data points. The quality of the quantitative WET measurements is determined by the uncertainty of the measured WET of a single ion (single-ion WET precision) and the deviation of a measured WET value to the well-known WET (WET accuracy). Subsequently, the fitted calibration curve is applied to an energy deposition radiograph of a phantom with a complex geometry. The spatial resolution (modulation transfer function at 10 % -MTF10% ) and WET accuracy (mean absolute percentage difference-MAPD) of the WET map are determined. RESULTS: In the optimal imaging WET-range from â¼280 to 300 mm, the fitted calibration curve reached a mean single-ion WET precision of 1.55 ± $\,{\pm}\,$ 0.00%. Applying the calibration to an ion radiograph (iRad) of a more complex WET distribution, the spatial resolution was determined to be MTF10% = 0.49 ± $\,{\pm}\,$ 0.03 lp/mm and the WET accuracy was assessed as MAPD to 0.21 %. CONCLUSIONS: Using a beam energy of 239.5 MeV/u and the proposed calibration procedure, quantitative αRads of WETs between â¼280 and 300 mm can be measured and show high potential for clinical use. The proposed approach with the resulting image qualities encourages further investigation toward the clinical application of helium-beam radiography.
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Helio , Agua , Calibración , Iones , Fantasmas de Imagen , RadiografíaRESUMEN
Fast-propagating waves in the phase of incommensurate structures, called phasons, have long been argued to enhance thermal transport. Although supersonic phason velocities have been observed, the lifetimes, from which mean free paths can be determined, have not been resolved. Using inelastic neutron scattering and thermal conductivity measurements, we establish that phasons in piezoelectric fresnoite make a major contribution to thermal conductivity by propagating with higher group velocities and longer mean free paths than phonons. The phason contribution to thermal conductivity is maximum near room temperature, where it is the single largest contributing degree of freedom.
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AIMS: To study the evolution of middle-ear surgery in 2019 in relation to the French Health Authority target of 66% day-surgery by 2020. MATERIAL AND METHODS: A single-center retrospective observational study included all patients undergoing otologic surgery between January 2014 and December 2018 in a university hospital center. 1064 of the 1368 patients were scheduled for outpatient surgery: 309 for otosclerosis, 355 for tympanoplasty with or without ossiculoplasty, 376 for cholesteatoma and 24 for other procedures. Two groups were constituted: day-surgery and conventional, according to hospital stay. Surgery time, follow-up duration, number of crossovers to conventional admission, number of emergency postoperative consultations, number of readmissions and data from the phone-call systematically made the day after surgery were analyzed. The main objective was to evaluate the safety of outpatient surgery for major middle-ear interventions compared to a control group managed under conventional admission during the same period. RESULTS: 27 patients (2.5%) required crossover, mainly due to disabling vertigo (57.7%). 53 patients (4.9%) consulted before the scheduled 8th day consultation, because of severe pain (23.5%) or dizziness (34.0%). Only 10 patients required emergency readmission. CONCLUSION: Provided that the inclusion criteria are met, all major middle-ear surgery procedures can be performed as day-surgery under satisfactory safety conditions.
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Colesteatoma del Oído Medio , Procedimientos Quirúrgicos Otológicos , Procedimientos Quirúrgicos Ambulatorios , Colesteatoma del Oído Medio/cirugía , Oído Medio , Humanos , Estudios Retrospectivos , Resultado del Tratamiento , TimpanoplastiaRESUMEN
OBJECTIVES: To evaluate whether the use of low-fidelity otoscopy simulation improved medical students' theoretical knowledge of middle ear anatomy and pathologies compared to traditional teaching methods. METHODS: This was a randomized controlled trial. Simulation workshops were conducted in April 2019 in the Lyon Sud University medical faculty, France. Students were randomly assigned to the simulation group (n=105) or to the control group (n=95). The students in the control group answered a questionnaire evaluating theoretical knowledge (25 true-false questions) before the simulation tutorial, while the students in the simulation group answered the same questions after the tutorial. Both groups also filled out a satisfaction questionnaire for feedback. RESULTS: 196 of the 200 students who participated in the study completed the knowledge assessment questionnaire. Scores were 32.0% higher in the simulation group than in the control group (mean scores, 12.0/20 vs. 9.1/20; P<0.0001). 184 of the 191 students who completed the satisfaction questionnaire (96.3%) were satisfied or very satisfied with the workshop, and all but one (99.5%) recommended keeping it in the curriculum. In the free comments fields, students highlighted the educational value of learning without the stress of patient discomfort. CONCLUSION: Otoscopy simulation is an effective training method, improving theoretical knowledge compared with conventional theoretical training.
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Entrenamiento Simulado , Estudiantes de Medicina , Competencia Clínica , Oído Medio , Evaluación Educacional , Humanos , OtoscopíaRESUMEN
AIMS: The purpose of repeated application of manosonic nebulizers (AMSA®) is to ensure active Eustachian tube rehabilitation and optimal middle-ear drug diffusion. In response to recent changes in marketing authorizations issued by the French National Drug Safety Agency (ANSM), the present study investigated how AMSA® is used in the Auvergne-Rhône-Alpes Region of France. MATERIAL AND METHODS: A prospective non-interventional regional 1-year survey was conducted in 701 general practitioners and community and hospital ENT physicians in the Auvergne-Rhône-Alpes Region, using a questionnaire sent by mail with a reminder at 2 months. Percentage responses were compared on Chi2 test with alpha risk of 5%. Non-respondents were excluded. ENDPOINTS: The main endpoints were rate of AMSA® prescription, and prescription modalities in a specific geographical territory (Auvergne-Rhône-Alpes Region) in 2018. RESULTS: 93% of the 114 respondents prescribed AMSA®, with 4,000 prescriptions in 1 year. 66.7% prescribed this treatment to avoid recourse to myringotomy. Mean treatment duration was 2 weeks (50.9% of respondents). The most frequent nebulized substance was saline serum (68.4% of respondents), sometimes associated to corticosteroids or mucolytics. CONCLUSION: The majority of physicians in the Auvergne-Rhône-Alpes Region, and notably the ENT physicians, were AMSA® prescribers for the treatment of Eustachian tube dysfunction and its consequences. However, the duration and modalities of use of AMSA® were very heterogeneous, and further studies are needed to standardize prescription.
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Amsacrina , Trompa Auditiva , Francia , Humanos , Nebulizadores y Vaporizadores , Estudios ProspectivosRESUMEN
This study aims to determine the frequency and causes of cochlear explants with re-implantation (ERI) after 5 years' follow up of the patients included in the French national EPIIC (étude post-inscription des implants cochléaires) registry tracking patients with cochlear implantation. This multicenter, descriptive prospective study was conducted on 5051 patients enrolled in the EPIIC database between January 2012 and December 2016. Ninety-five patients (1.9%) received a primary implant and an ERI during the study. Of these, four benefitted from two ERIs. The number of ERIs was significantly higher in the pediatric population than among adults. The explantation and reimplantation were performed simultaneously in 86% of cases. The reasons for explantation were: in 46.4% of cases linked to a malfunction of the implant, and in 39.3% of cases for medical or surgical reasons. The number of electrodes inserted was significantly higher after the ERI than after the first implantation. There was just one post-ERI infection for these 95 explanted and re-implanted patients. As well as explantation with reimplantation rarely being necessary, it generally presents no major surgical difficulty and in most cases it allows a better integration than in the first implantation.
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Implantación Coclear/estadística & datos numéricos , Implantes Cocleares/estadística & datos numéricos , Remoción de Dispositivos/estadística & datos numéricos , Sistema de Registros/estadística & datos numéricos , Reoperación/estadística & datos numéricos , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Implantes Cocleares/efectos adversos , Francia , Humanos , Lactante , Persona de Mediana Edad , Estudios Prospectivos , Falla de Prótesis , Reimplantación/estadística & datos numéricos , Factores de Tiempo , Adulto JovenRESUMEN
Lead halide perovskites are strong candidates for high-performance low-cost photovoltaics, light emission, and detection applications. A hot-phonon bottleneck effect significantly extends the cooling time of hot charge carriers, which thermalize through carrier-optic phonon scattering, followed by optic phonon decay to acoustic phonons and finally thermal conduction. To understand these processes, we adjust the lattice dynamics independently of electronics by changing isotopes. We show that doubling the mass of hydrogen in methylammonium lead iodide by replacing protons with deuterons causes a large 20 to 50% softening of the longitudinal acoustic phonons near zone boundaries, reduces thermal conductivity by ~50%, and slows carrier relaxation kinetics. Phonon softening is attributed to anticrossing with the slowed libration modes of the deuterated molecules and the reduced thermal conductivity to lowered phonon velocities. Our results reveal how tuning the organic molecule dynamics enables control of phonons important to thermal conductivity and the hot-phonon bottleneck.
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Local thermal magnetization fluctuations in Li-doped MnTe are found to increase its thermopower α strongly at temperatures up to 900 K. Below the Néel temperature (T N ~ 307 K), MnTe is antiferromagnetic, and magnon drag contributes αmd to the thermopower, which scales as ~T 3. Magnon drag persists into the paramagnetic state up to >3 × T N because of long-lived, short-range antiferromagnet-like fluctuations (paramagnons) shown by neutron spectroscopy to exist in the paramagnetic state. The paramagnon lifetime is longer than the charge carrier-magnon interaction time; its spin-spin spatial correlation length is larger than the free-carrier effective Bohr radius and de Broglie wavelength. Thus, to itinerant carriers, paramagnons look like magnons and give a paramagnon-drag thermopower. This contribution results in an optimally doped material having a thermoelectric figure of merit ZT > 1 at T > ~900 K, the first material with a technologically meaningful thermoelectric energy conversion efficiency from a spin-caloritronic effect.
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Melanoma , Proteínas Proto-Oncogénicas B-raf , Humanos , Imidazoles , Oximas , Piridonas , PirimidinonasRESUMEN
OBJECTIVE: to assess the evolution of sinonasal manifestations in children with cystic fibrosis, since the improvement of their prognosis over the last decades. METHODS: an observational, monocentric study with a retrospective cohort. We included 173 children (from 4 to 18 years old) with cystic fibrosis followed at the pediatric cystic fibrosis center of lyon, france. We collected respiratory, infectious and nutritional data, sinonasal complaints and physical examination at the onset of sinonasal symptoms (t-0), at the most severe of evolution (t-max) and at the end of followup (t-end). RESULTS: sinonasal symptomatology appeared early around 5.4 years old, then rapidly reached the maximum at 6.9 years and finally improved during childhood (pâ¯<â¯0.0001), reaching scores at t-end significantly better than at t-0 (pâ¯<â¯0.0001). This evolution was significant for nasal obstruction, rhinorrhea and snoring. The other symptoms were rarer, with no significant 38,7% at t-max (pâ¯<â¯0.0001), and 29,5% at t-end (pâ¯=â¯0.52). The lildholdt score, turbinate hypertrophy and medial bulging of medial wall of the maxillary sinus followed the same evolution (pâ¯<â¯0.003). There was no association between sinonasal evolution and cystic fibrosis disease at infectious, respiratory or nutritional level. CONCLUSION: it is the only recent study evaluating the evolution of each sinonasal manifestations in children with cystic fibrosis. Rhinosinusitis improved during childhood, reaching better scores than at the beginning of management. This particular improvement may be related to good effectiveness to ent management, but also to a positive effect of nasal cavity growth, independently to extra-ent manifestations.
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Fibrosis Quística/complicaciones , Obstrucción Nasal/etiología , Ronquido/etiología , Adolescente , Niño , Preescolar , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Cavidad Nasal/crecimiento & desarrollo , Pronóstico , Estudios Retrospectivos , Sinusitis/etiologíaRESUMEN
The authors present the guidelines of the French Society of ENT and Head and Neck Surgery (SFORL) regarding indications for cochlear implantation in adults. After a literature review by a multidisciplinary workgroup, guidelines were drawn up based on retrieved articles and group-members' experience, then read over by an independent reading group to edit the final version. Guidelines were graded A, B, C or "expert opinion" according to decreasing level of evidence. There is no upper age limit to cochlear implantation in the absence of proven dementia and if autonomy is at least partial. Bilateral implantation may be proposed if unilateral implantation fails to provide sufficiently good spatial localization, speech perception in noise and quality of life, and should be preceded by binaural hearing assessment. Rehabilitation by acoustic and electrical stimulation may be proposed when low-frequency hearing persists. Quality of life should be assessed before and after implantation.
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Implantación Coclear/normas , Otolaringología/normas , Anciano , Implantación Coclear/métodos , Disfunción Cognitiva/etiología , Disfunción Cognitiva/rehabilitación , Francia , Pérdida Auditiva/complicaciones , Pérdida Auditiva/rehabilitación , Humanos , Persona de Mediana Edad , Calidad de Vida , Sociedades MédicasRESUMEN
Lead chalcogenides have exceptional thermoelectric properties and intriguing anharmonic lattice dynamics underlying their low thermal conductivities. An ideal material for thermoelectric efficiency is the phonon glass-electron crystal, which drives research on strategies to scatter or localize phonons while minimally disrupting electronic-transport. Anharmonicity can potentially do both, even in perfect crystals, and simulations suggest that PbSe is anharmonic enough to support intrinsic localized modes that halt transport. Here, we experimentally observe high-temperature localization in PbSe using neutron scattering but find that localization is not limited to isolated modes - zero group velocity develops for a significant section of the transverse optic phonon on heating above a transition in the anharmonic dynamics. Arrest of the optic phonon propagation coincides with unusual sharpening of the longitudinal acoustic mode due to a loss of phase space for scattering. Our study shows how nonlinear physics beyond conventional anharmonic perturbations can fundamentally alter vibrational transport properties.
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OBJECTIVES: Kawasaki disease (KD) is a febrile multisystemic vasculitis of unknown etiology whose coronary prognosis is improved by early diagnosis and management. The objective of this study was to describe ENT manifestations encountered and to look for a delayed diagnosis associated with these manifestations. METHODS: A retrospective descriptive single-center study was conducted in Lyon between January 2009 and December 2017. All children treated for Kawasaki disease were included in the study. Clinical, biological and cardiac ultrasound data were collected. According to the diagnosis made at the first medical visit, children were classified into two groups: diagnosis of ENT spectrum or non-ENT diagnosis. The diagnostic times were compared by a Student test. RESULTS: 142 patients were included: 64 in the ENT diagnostic group, 78 in the non-ENT diagnostic group. When the initial diagnosis was of ENT spectrum, the diagnostic time of KD was significantly longer: 8.51 days vs 5.77 days - (pâ¯<â¯0.01). The total duration of fever was also longer - 10.92 vs 8.32 days - (pâ¯=â¯0.013) - and the frequency of antibiotics intake more important - 92.2% vs 46.2% - (pâ¯<â¯0.01). Four children underwent surgery in the ENT diagnostic group: two retro-pharyngeal abscesses, one paracentesis and one cervicectomy. CONCLUSIONS: ENT manifestations are frequently at the forefront of KD and constitute a misleading clinical picture responsible for delayed diagnosis and potentially inappropriate medico-surgical management. It is necessary to provide more education to practitioners for earlier recognition of Kawasaki disease.
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Síndrome Mucocutáneo Linfonodular/complicaciones , Síndrome Mucocutáneo Linfonodular/diagnóstico , Enfermedades Otorrinolaringológicas/diagnóstico , Enfermedades Otorrinolaringológicas/etiología , Antibacterianos/uso terapéutico , Niño , Preescolar , Diagnóstico Tardío , Diagnóstico Diferencial , Femenino , Fiebre/etiología , Humanos , Lactante , Masculino , Síndrome Mucocutáneo Linfonodular/terapia , Enfermedades Otorrinolaringológicas/terapia , Estudios Retrospectivos , Procedimientos InnecesariosRESUMEN
The abundance of organic carbon (OC) in vegetation and soils (~2,600 PgC) compared to carbon in the atmosphere (~830 PgC) highlights the importance of terrestrial OC in global carbon budgets. The residence time of OC in continental reservoirs, which sets the rates of carbon exchange between land and atmosphere, represents a key uncertainty in global carbon cycle dynamics. Retention of terrestrial OC can also distort bulk OC- and biomarker-based paleorecords, yet continental storage timescales remain poorly quantified. Using "bomb" radiocarbon (14C) from thermonuclear weapons testing as a tracer, we model leaf-wax fatty acid and bulk OC 14C signatures in a river-proximal marine sediment core from the Bay of Bengal in order to constrain OC storage timescales within the Ganges-Brahmaputra (G-B) watershed. Our model shows that 79-83% of the leaf-waxes in this core were stored in continental reservoirs for an average of 1,000-1,200 calendar years, while the remainder was stored for an average of 15 years. This age structure distorts high-resolution organic paleorecords across geologically rapid events, highlighting that compound-specific proxy approaches must consider storage timescales. Furthermore, these results show that future environmental change could destabilize large stores of old - yet reactive - OC currently stored in tropical basins.
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Staphylococcus aureus causes a chronic, contagious disease of the udder, or mastitis, in dairy cows. This infection is often refractory to antibiotic treatment, and has a significant economic impact on milk production worldwide. An effective vaccine to prevent S. aureus mastitis would improve animal health, reduce antibiotic dependence and inform human vaccine approaches. The iron-regulated surface determinant A (IsdA) and clumping factor A (ClfA) are conserved S. aureus extracellular-matrix adhesins and target vaccine antigens. Here we report the results of two bovine immunogenicity trials using purified IsdA and ClfA-cholera toxin A2/B chimeras (IsdA-CTA2/B and ClfA-CTA2/B). Cows were intranasally inoculated with IsdA-CTA2/Bâ¯+â¯ClfA-CTA2/B at dry off and followed for 70â¯days. Trial 1 utilized three groups with one or two booster doses at a total concentration of 600 or 900⯵g. Trial 2 utilized two groups with one booster at a total concentration of 1200⯵g. Humoral immune responses in serum and milk were examined by ELISA. Responses in serum were significant between groups and provide evidence of antigen-specific IgG induction after vaccination in both trials. Cellular proliferation was detected by flow cytometry using antigen-stimulated PBMCs from day 60 of Trial 2 and revealed an increase in CD4+ T cells from vaccinated cows. IsdA and ClfA stimulation induced IL-4 expression, but not IFN-γ or IL-17, in PBMCs from day 60 as determined by cytokine expression analysis. Opsonophagocytosis of S. aureus confirmed the functional in vitro activity of anti-IsdA antibodies from Trial 2 serum and milk. The vaccine was well tolerated and safe, and results support the potential of mucosally-delivered CTA2/B chimeras to protect cows from mastitis caused by S. aureus.
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Anticuerpos Antibacterianos/biosíntesis , Mastitis Bovina/prevención & control , Proteínas Recombinantes de Fusión/inmunología , Infecciones Estafilocócicas/prevención & control , Infecciones Estafilocócicas/veterinaria , Vacunas Estafilocócicas/biosíntesis , Administración Intranasal , Animales , Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/administración & dosificación , Antígenos Bacterianos/genética , Antígenos Bacterianos/inmunología , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/microbiología , Bovinos , Proliferación Celular/efectos de los fármacos , Toxina del Cólera/administración & dosificación , Toxina del Cólera/genética , Toxina del Cólera/inmunología , Coagulasa/administración & dosificación , Coagulasa/genética , Coagulasa/inmunología , Femenino , Expresión Génica , Inmunidad Humoral/efectos de los fármacos , Inmunización Secundaria/métodos , Inmunogenicidad Vacunal , Inmunoglobulina G/biosíntesis , Inmunoglobulina G/sangre , Interleucina-4/biosíntesis , Interleucina-4/metabolismo , Glándulas Mamarias Animales/inmunología , Glándulas Mamarias Animales/microbiología , Mastitis Bovina/inmunología , Mastitis Bovina/microbiología , Leche/química , Leche/inmunología , Leche/microbiología , Isoformas de Proteínas/administración & dosificación , Isoformas de Proteínas/genética , Isoformas de Proteínas/inmunología , Proteínas Recombinantes de Fusión/administración & dosificación , Proteínas Recombinantes de Fusión/genética , Infecciones Estafilocócicas/inmunología , Infecciones Estafilocócicas/microbiología , Vacunas Estafilocócicas/administración & dosificación , Vacunas Estafilocócicas/genética , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/inmunología , Staphylococcus aureus/patogenicidadRESUMEN
Controlling the thermal energy of lattice vibrations separately from electrons is vital to many applications including electronic devices and thermoelectric energy conversion. To remove heat without shorting electrical connections, heat must be carried in the lattice of electrical insulators. Phonons are limited to the speed of sound, which, compared to the speed of electronic processes, puts a fundamental constraint on thermal management. Here we report a supersonic channel for the propagation of lattice energy in the technologically promising piezoelectric mineral fresnoite (Ba2TiSi2O8) using neutron scattering. Lattice energy propagates 2.8-4.3 times the speed of sound in the form of phasons, which are caused by an incommensurate modulation in the flexible framework structure of fresnoite. The phasons enhance the thermal conductivity by 20% at room temperature and carry lattice-energy signals at speeds beyond the limits of phonons.