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1.
Nano Lett ; 22(1): 6-13, 2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-34958595

RESUMEN

An induced-transmission filter (ITF) uses an ultrathin metallic layer positioned at an electric-field node within a dielectric thin-film bandpass filter to select one transmission band while suppressing other bands that would have been present without the metal layer. We introduce a switchable mid-infrared ITF where the metal can be "switched on and off", enabling the modulation of the filter response from a single band to multiband. The switching is enabled by the reversible insulator-to-metal phase transition of a subwavelength film of vanadium dioxide (VO2). Our work generalizes the ITF─a niche type of bandpass filter─into a new class of tunable devices. Furthermore, our fabrication process─which begins with thin-film VO2 on a suspended membrane─enables the integration of VO2 into any thin-film assembly that is compatible with physical vapor deposition processes and is thus a new platform for realizing tunable thin-film filters.

2.
Radiology ; 297(3): 622-629, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33078998

RESUMEN

Background CT and bone scintigraphy have limitations in evaluating systemic anticancer therapy (SACT) response in bone metastases from metastatic breast cancer (MBC). Purpose To evaluate whether whole-body MRI enables identification of progressive disease (PD) earlier than CT and bone scintigraphy in bone-only MBC. Materials and Methods This prospective study evaluated participants with bone-only MBC between May 2016 and January 2019 (ClinicalTrials.gov identifier: NCT03266744). Participants were enrolled at initiation of first or subsequent SACT based on standard CT and bone scintigraphy imaging. Baseline whole-body MRI was performed within 2 weeks of entry; those with extraosseous disease were excluded. CT and whole-body MRI were performed every 12 weeks until definitive PD was evident with one or both modalities. In case of PD, bone scintigraphy was used to assess for bone disease progression. Radiologists independently interpreted images from CT, whole-body MRI, or bone scintigraphy and were blinded to results with the other modalities. Systematic differences in performance between modalities were analyzed by using the McNemar test. Results Forty-five participants (mean age, 60 years ± 13 [standard deviation]; all women) were evaluated. Median time on study was 36 weeks (range, 1-120 weeks). Two participants were excluded because of unequivocal evidence of liver metastases at baseline whole-body MRI, two participants were excluded because they had clinical progression before imaging showed PD, and one participant was lost to follow-up. Of the 33 participants with PD at imaging, 67% (22 participants) had PD evident at whole-body MRI only and 33% (11 participants) had PD at CT and whole-body MRI concurrently; none had PD at CT only (P < .001, McNemar test). There was only slight agreement between whole-body MRI and CT (Cohen κ, 0.15). PD at bone scintigraphy was reported in 50% of participants (13 of 26) with bone progression at CT and/or whole-body MRI (P < .001, McNemar test). Conclusion Whole-body MRI enabled identification of progressive disease before CT in most participants with bone-only metastatic breast cancer. Progressive disease at bone scintigraphy was evident in only half of participants with bone progression at whole-body MRI. © RSNA, 2020 Online supplemental material is available for this article.


Asunto(s)
Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/secundario , Neoplasias Óseas/terapia , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Imagen de Cuerpo Entero/métodos , Medios de Contraste , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética , Persona de Mediana Edad , Estudios Prospectivos , Cintigrafía , Radiofármacos , Tomografía Computarizada por Rayos X
3.
Breast Cancer Res Treat ; 147(2): 335-43, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25129341

RESUMEN

Quantitative DCE-MRI parameters including K(trans) (transfer constant min(-1)) can predict both response and outcome in breast cancer patients treated with neoadjuvant chemotherapy (NAC). Quantitative methods are time-consuming to calculate, requiring expensive software and interpretive expertise. For diagnostic purposes, signal intensity-time curves (SITCs) are used for tissue characterisation. In this study, we compare the ability of NAC-related changes in SITCs with K(trans) to predict response and outcomes. 73 women with primary breast cancer underwent DCE-MRI studies before and after two cycles of NAC. Patients received anthracycline and/or docetaxel-based chemotherapy. At completion of NAC, patients had local treatment with surgery & radiotherapy and further systemic treatments. SITCs for paired DCE-MRI studies were visually scored using a five-curve type classification schema encompassing wash-in and wash-out phases and correlated with K(trans) values and to the endpoints of pathological response, OS and DFS. 58 paired patients studies were evaluable. The median size by MRI measurement for 52 tumours was 38 mm (range 17-86 mm) at baseline and 26 mm (range 10-85 mm) after two cycles of NAC. Median baseline K(trans) (min(-1)) was 0.214 (range 0.085-0.469), and post-two cycles of NAC was 0.128 (range 0.013-0.603). SITC shapes were significantly related to K(trans) values both before (χ (2) = 43.3, P = 0.000) and after two cycles of NAC (χ (2) = 60.5, P = 0.000). Changes in curve shapes were significantly related to changes in K(trans) (χ (2) = 53.5, P = 0.000). Changes in curve shape were significantly correlated with clinical (P = 0.005) and pathological response (P = 0.005). Reductions in curve shape of ≥1 point were significant for overall improved survival using Kaplan-Meier analysis with a 5-year OS of 80.9 versus 68.6 % (P = 0.048). SITCs require no special software to generate and provide a useful method of assessing the effectiveness of NAC for primary breast cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Adulto , Anciano , Antraciclinas/administración & dosificación , Neoplasias de la Mama/cirugía , Quimioterapia Adyuvante , Medios de Contraste/administración & dosificación , Ciclofosfamida/administración & dosificación , Docetaxel , Epirrubicina/administración & dosificación , Femenino , Fluorouracilo/administración & dosificación , Humanos , Estimación de Kaplan-Meier , Imagen por Resonancia Magnética/métodos , Persona de Mediana Edad , Terapia Neoadyuvante/métodos , Estudios Prospectivos , Taxoides/administración & dosificación , Adulto Joven
4.
Opt Lett ; 39(3): 517-20, 2014 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-24487854

RESUMEN

Spoof surface plasmons (SP) are SP-like waves that propagate along metal surfaces with deeply sub-wavelength corrugations and whose dispersive properties are determined primarily by the corrugation dimensions. Two parallel corrugated surfaces separated by a sub-wavelength dielectric gap create a "spoof" analog of the plasmonic metal-insulator-metal waveguides, dubbed a "spoof-insulator-spoof" (SIS) waveguide. Here we study the optical forces generated by the propagating "bonding" and "anti-bonding" waveguide modes of the SIS geometry and the role that surface structuring plays in determining the modal properties. By changing the dimensions of the grooves, strong attractive and repulsive optical forces between the surfaces can be generated at nearly any frequency.

5.
Semin Radiat Oncol ; 34(1): 56-63, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38105094

RESUMEN

The landscape of lung radiotherapy (RT) has rapidly evolved over the past decade with modern RT and surgical techniques, systemic therapies, and expanding indications for RT. To date, 2 MRI-guided RT (MRgRT) units, 1 using a 0.35T magnet and 1 using a 1.5T magnet, are available for commercial use with more systems in the pipeline. MRgRT offers distinct advantages such as real-time target tracking, margin reduction, and on-table treatment adaptation, which may help overcome many of the common challenges associated with thoracic RT. Nonetheless, the use of MRI for image guidance and the current MRgRT units also have intrinsic limitations. In this review article, we will discuss clinical experiences to date, advantages, challenges, and future directions of MRgRT to the lung.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Oncología por Radiación , Radioterapia Guiada por Imagen , Humanos , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/radioterapia , Radioterapia Guiada por Imagen/métodos , Imagen por Resonancia Magnética/métodos
6.
J Med Imaging Radiat Sci ; 55(4): 101716, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39032239

RESUMEN

INTRODUCTION: This work reports on an unusual finding observed during image quality assessment in the preparation for the clinical implementation of breast magnetic resonance image-guided radiotherapy (MRIgRT) on a 1.5 Tesla (T) magnetic resonance linear accelerator (MR-Linac) (Elekta AB, Stockholm, Sweden). CASE AND OUTCOMES: A patient with T2 N0 M0 right breast invasive ductal carcinoma, receiving adjuvant radiotherapy, underwent two imaging sessions on the MR-Linac. The imaging protocol included T1- and T2-weighted (W) turbo spin echo (TSE) sequences, a T1W mDixon, and a T2W TSE navigated sequence acquired on end-expiration. All images were reconstructed in the axial plane. Images were assessed for image quality and appropriateness for use within the treatment pathway using visual grading analysis (VGA). An artefact in the right breast was noted independently by all observers. The patient's skin and medical notes were reviewed for possible explanation. The findings were discussed with the patient's responsible clinician, and subsequent referral to the local multi-disciplinary team (MDT) for radiologist review was made. On further investigation, the patient's images demonstrated a signal void in the subareolar region of the right breast coinciding with the surgical site. This was distal from the tumour bed and deemed unlikely to be related to a Magseed marker or intraoperative clips. The patient reported no history of nipple tattoo or piercing. There was nothing on clothing that this could be attributed to. DISCUSSION: Following MDT review, where all potential sources of signal void were considered, it was concluded that the cause was Magtrace, a superparamagnetic iron oxide tracer, recommended for sentinel lymph node localisation in patients with breast cancer in the United Kingdom. The artefact was characteristic of a magnetic susceptibility artefact. These can arise from local magnetic field inhomogeneities caused by the presence of the metal compounds in MagTrace. For breast MRIgRT on the MR-Linac, treatment verification and the possibility of real-time replanning is a critical aspect. The magnetic susceptibility artefact significantly inhibited plan adaption and confidence in the online image registration process making the patient ineligible for treatment on the MR-Linac. CONCLUSION: As part of ongoing work-up for breast MRIgRT, the screening of patients for Magtrace is now included. Optimisation of MR imaging sequences for radiotherapy planning and image review to minimise distortion are being developed.

7.
Front Oncol ; 14: 1328871, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38660130

RESUMEN

Introduction: The use of patient-reported outcomes (PROs) has been shown to enhance the accuracy of symptom collection and improve overall survival and quality of life. This is the first study comparing concordance and patient preference for two PRO tools: Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE®) and the adapted-REQUITE Lung Questionnaire. Materials and Methods: Patients with lung cancer were recruited to the study while attending outpatient clinics at a tertiary cancer centre. Clinician-reported outcomes were generated through initial patient assessment with CTCAE v4.03. Participants then completed the PRO-CTCAE® and adapted-REQUITE questionnaires. Concordance between the 2 questionnaires was assessed by calculating Pearson correlation coefficient. PRO-CTCAE® and CTCAE concordance was demonstrated by calculating Pearson correlation coefficient from the linear predictors of an ordinal logistic regression. P-values were also calculated. Results: Out of 74 patients approached, 65 provided written informed consent to participate in the study. 63 (96.9%) patients completed both PRO-CTCAE® and adapted-REQUITE questionnaires. Pearson correlation coefficient between PRO tools was 0.8-0.83 (p <.001). Correlation between CTCAE and PRO-CTCAE® ranged between 0.66-0.82 (p <.001). Adapted-REQUITE and CTCAE correlation was higher for all symptoms ranging between 0.79-0.91 (p <.001). Acceptable discrepancies within one grade were present in 96.8%-100% of symptom domains for REQUITE and in 92.1%-96.8% for all domains in the PRO-CTCAE®. 54% of the total participant cohort favored the adapted-REQUITE questionnaire due to reduced subjectivity in the questions and ease of use. Conclusion: The adapted-REQUITE questionnaire has shown a superior correlation to clinician-reported outcomes and higher patient preference than the PRO-CTCAE®. The results of this study suggest the use of the REQUITE questionnaire for patients with lung cancer in routine clinical practice.

8.
JCO Clin Cancer Inform ; 8: e2300162, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38574311

RESUMEN

PURPOSE: Electronic patient-reported outcome measures (ePROMs) are digitalized health questionnaires used to gauge patients' subjective experience of health and disease. They are becoming prevalent in cancer care and have been linked to a host of benefits including improved survival. MyChristie-MyHealth is the ePROM established at the Christie NHS Foundation Trust in 2019. We conducted an evaluation of this service to understand user experiences, as well as strategies to improve its functioning. METHODS: Data collection: Patients who had opted never to complete MyChristie-MyHealth (n = 87), and those who had completed at least one (n = 87) were identified. Demographic data included age, sex, ethnicity, postcode, diagnosis, treatment intent, and trial status. Semistructured interviews were held with noncompleters (n = 30) and completers (n = 31) of MyChristie-MyHealth, as well as clinician users (n = 6), covering themes such as accessibility, acceptability and usefulness, and open discourse on ways in which the service could be improved. RESULTS: Noncompleters of MyChristie-MyHealth were older (median age 72 v 66 years, P = .005), receiving treatment with curative rather than palliative intent (odds ratio [OR], 1.45; P = .045), and less likely to be enrolled on a clinical trial (OR, 0.531; P = .011). They were less likely to own a smartphone (33% v 97%) or have reliable Internet access (45% v 100%). Satisfaction with MyChristie-MyHealth was high in both groups: 93% (n = 29) of completers and 87% (n = 26) noncompleters felt generally happy to complete. Completers of MyChristie-MyHealth wanted their results to be acknowledged by their clinicians. Clinicians wanted results to be displayed in a more user-friendly way. CONCLUSION: We have broadly characterized noncompleters of the Christie ePROM to identify those in need of extra support or encouragement in the clinic. An action plan resulting from this review has been compiled and will inform the future development of MyChristie-MyHealth.


Asunto(s)
Neoplasias , Medición de Resultados Informados por el Paciente , Anciano , Humanos , Neoplasias/diagnóstico , Neoplasias/terapia , Encuestas y Cuestionarios
9.
Opt Express ; 21(6): 7258-75, 2013 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-23546110

RESUMEN

We present here an optomechanical system fabricated with novel stress management techniques that allow us to suspend an ultrathin defect-free silicon photonic-crystal membrane above a Silicon-on-Insulator (SOI) substrate with a gap that is tunable to below 200 nm. Our devices are able to generate strong attractive and repulsive optical forces over a large surface area with simple in- and out- coupling and feature the strongest repulsive optomechanical coupling in any geometry to date (gOM/2π ≈65 GHz/nm). The interplay between the optomechanical and photo-thermal-mechanical dynamics is explored, and the latter is used to achieve cooling and amplification of the mechanical mode, demonstrating that our platform is well-suited for potential applications in low-power mass, force, and refractive-index sensing as well as optomechanical accelerometry.


Asunto(s)
Membranas Artificiales , Sistemas Microelectromecánicos/instrumentación , Refractometría/instrumentación , Silicio/química , Transductores , Cristalización , Diseño de Equipo , Análisis de Falla de Equipo , Calor , Luz
10.
J Patient Rep Outcomes ; 7(1): 42, 2023 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-37140730

RESUMEN

BACKGROUND: Cancer and its treatment can have significant impacts on health status, quality of life and functioning of patients. Direct information from patients regarding these aspects can be collected via electronic platforms in the form of electronic Patient Reported Outcome Measures (ePROMs). Research has shown that the use of ePROMS in cancer care leads to improved communication, better symptom control, prolonged survival and a reduction in hospital admissions and emergency department attendance. Acceptability and feasibility of routine ePROM collection has been reported by both patients and clinicians but to date their use has predominantly been limited to clinical trials. MyChristie-MyHealth is an initiative from a UK comprehensive cancer centre The Christie NHS Foundation Trust which incorporates the regular collection of ePROMs into routine cancer care. This study, carried out as part of a service evaluation, explores patient and clinician experiences of using the MyChristie-MyHealth ePROMs service. RESULTS: 100 patients with lung and head and neck cancers completed a Patient Reported Experience questionnaire. All patients reported that MyChristie-MyHealth was easy to understand and, almost all found it timely to complete and easy to follow. Most patients (82%) reported it improved their communication with their oncology team and helped them to feel more involved with their care (88%). A large proportion of clinicians (8/11) felt ePROMs helped communication with their patients and over half (6/10) felt they led to consultations being more patient focused. Clinicians also felt that the use of ePROMs resulted in patients being more engaged in consultations (7/11) and their cancer care in general (5/11). Five clinicians reported that the use of ePROMs altered their clinical decision making. CONCLUSIONS: Regular ePROMs collection as part of routine cancer care is acceptable to both patients and clinicians. Both patients and clinicians feel their use improved communication and increased the feeling of patient involvement with their care. Further work is needed to explore the experiences of patients that did not complete the ePROMs as part of the initiative and to continue to optimize the service for both patients and clinicians.


Asunto(s)
Neoplasias de Cabeza y Cuello , Calidad de Vida , Humanos , Oncología Médica , Participación del Paciente , Medición de Resultados Informados por el Paciente
11.
JCO Clin Cancer Inform ; 7: e2200150, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37071029

RESUMEN

PURPOSE: The Christie NHS Foundation Trust launched their electronic patient-reported outcome measures (ePROMs) service in January 2019 in the routine clinical setting. The lung cancer questionnaires consist of 14 symptom items, adapted from the Common Terminology Criteria for Adverse Events (version 5.0) and the EuroQol EQ-5D-5L quality-of-life (QoL) tool. Patients with lung cancer are invited to complete questionnaires assessing their symptoms and QoL using an online platform. METHODS: The ePROM responses and clinical, pathologic, and treatment data for patients who completed the questionnaires between January 2019 and December 2020 were extracted from electronic medical records. The symptom and QoL scores of patients who completed baseline pretreatment ePROMs and also those who completed ePROMs pre- and postpalliative lung systemic anticancer therapy (SACT) or radical thoracic radiotherapy were evaluated. Pretreatment questionnaires were analyzed according to age, Eastern Cooperative Oncology Group performance status (ECOG PS), and Adult Comorbidity Evaluation-27 (ACE-27) comorbidity score. RESULTS: One thousand four hundred eighty patients with lung cancer were included. There were no statistically significant differences in symptoms and QoL scores between age groups. Cough (P = .006) and EQ-5D-5L mobility scores (P = .006) were significantly worse for patients with an ECOG PS of 0-1. Dyspnea (P = .035), hemoptysis (P = .023), nausea (P = .041), mobility (P = .004), and self-care (P = .0420) were significantly worse for those with higher ACE-27 scores (2-3 v 0-1). Palliative SACT was associated with a significant improvement in cough (P < .001) and hemoptysis (P = .025), but significantly negatively affected mobility (P = .013). Patients receiving radical thoracic radiotherapy reported a significant improvement in hemoptysis (P = .042) but worse pain (P = .002) and fatigue (P = .01). Other changes in symptom and QoL scores were not significant. CONCLUSION: The symptoms and QoL reported at baseline and before and after both palliative SACT and radical thoracic radiotherapy are clinically relevant and meaningful. We have demonstrated that routine implementation of ePROMs into clinical practice is feasible and can inform clinical practice and future research.


Asunto(s)
Neoplasias Pulmonares , Calidad de Vida , Adulto , Humanos , Tos , Hemoptisis , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/patología , Medición de Resultados Informados por el Paciente
12.
Front Oncol ; 12: 835844, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35712515

RESUMEN

Background: Lung cancer survival remains poor. The introduction of Intensity-Modulated Radiotherapy (IMRT) allows treatment of more complex tumours as it improves conformity around the tumour and greater normal tissue sparing. However, there is limited evidence assessing the clinical impact of IMRT. In this study, we evaluated whether the introduction of IMRT had an influence on the proportion of patients treated with curative-intent radiotherapy over time, and whether this had an effect on patient survival. Materials and Methods: Patients treated with thoracic radiotherapy at our institute between 2005 and 2020 were retrospectively identified and grouped into three time periods: A) 2005-2008 (pre-IMRT), B) 2009-2012 (selective use of IMRT), and C) 2013-2020 (full access to IMRT). Data on performance status (PS), stage, age, gross tumour volume (GTV), planning target volume (PTV) and survival were collected. The proportion of patients treated with a curative dose between these periods was compared. Multivariable survival models were fitted to evaluate the hazard for patients treated in each time period, adjusting for PS, stage, age and tumour volume. Results: 12,499 patients were included in the analysis (n=2675 (A), n=3127 (B), and n=6697 (C)). The proportion of patients treated with curative-intent radiotherapy increased between the 3 time periods, from 38.1% to 50.2% to 65.6% (p<0.001). When stage IV patients were excluded, this increased to 40.1% to 58.1% to 82.9% (p<0.001). This trend was seen across all PS and stages. The GTV size increased across the time periods and PTV size decreased. Patients treated with curative-intent during period C had a survival improvement compared to time period A when adjusting for clinical variables (HR=0.725 (0.632-0.831), p<0.001). Conclusion: IMRT was associated with to more patients receiving curative-intent radiotherapy. In addition, it facilitated the treatment of larger tumours that historically would have been treated palliatively. Despite treating larger, more complex tumours with curative-intent, a survival benefit was seen for patients treated when full access to IMRT was available (2013-2020). This study highlights the impact of IMRT on thoracic oncology practice, accepting that improved survival may also be attributed to a number of other contributing factors, including improvements in staging, other technological radiotherapy advances and changes to systemic treatment.

13.
Opt Express ; 19(16): 14860-70, 2011 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-21934847

RESUMEN

We describe the properties of guided modes in metallic parallel plate structures with subwavelength corrugation on the surfaces of both conductors, which we refer to as spoof-insulator-spoof (SIS) waveguides, in close analogy to metal-insulator-metal (MIM) waveguides in plasmonics. A dispersion relation for SIS waveguides is derived, and the modes are shown to arise from the coupling of conventional waveguide modes with the localized modes of the grooves in the SIS structure. SIS waveguides have numerous design parameters and can be engineered to guide modes with very low group velocities and adiabatically convert light between conventional photonic modes and plasmonic ones.


Asunto(s)
Metales/química , Espectrofotometría Infrarroja/métodos , Anisotropía , Radiación Electromagnética , Diseño de Equipo , Rayos Láser , Luz , Modelos Estadísticos , Modelos Teóricos , Oscilometría/métodos , Fotones , Refractometría , Resonancia por Plasmón de Superficie/métodos
14.
Opt Express ; 19(3): 2225-41, 2011 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-21369040

RESUMEN

We demonstrate that tunable attractive (bonding) and repulsive (anti-bonding) forces can arise in highly asymmetric structures coupled to external radiation, a consequence of the bonding/anti-bonding level repulsion of guided-wave resonances that was first predicted in symmetric systems. Our focus is a geometry consisting of a photonic-crystal (holey) membrane suspended above an unpatterned layered substrate, supporting planar waveguide modes that can couple via the periodic modulation of the holey membrane. Asymmetric geometries have a clear advantage in ease of fabrication and experimental characterization compared to symmetric double-membrane structures. We show that the asymmetry can also lead to unusual behavior in the force magnitudes of a bonding/antibonding pair as the membrane separation changes, including nonmonotonic dependences on the separation. We propose a computational method that obtains the entire force spectrum via a single time-domain simulation, by Fourier-transforming the response to a short pulse and thereby obtaining the frequency-dependent stress tensor. We point out that by operating with two, instead of a single frequency, these evanescent forces can be exploited to tune the spring constant of the membrane without changing its equilibrium separation.


Asunto(s)
Membranas Artificiales , Modelos Teóricos , Pinzas Ópticas , Simulación por Computador , Luz , Estrés Mecánico
15.
Radiother Oncol ; 160: 78-81, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33901563

RESUMEN

Outcomes of non-small cell lung cancer (NSCLC) patients with chronic obstructive pulmonary disease (COPD n = 587) and interstitial lung disease (ILD n = 34) treated with curative-intent radiotherapy were retrospectively investigated. Presence of ILD but not decreased forced expiratory volume in 1-second correlated with poor overall survival. Increased breathlessness and oxygen requirements after radiotherapy were observed in severe/very severe COPD and ILD.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Enfermedades Pulmonares Intersticiales , Neoplasias Pulmonares , Enfermedad Pulmonar Obstructiva Crónica , Carcinoma de Pulmón de Células no Pequeñas/complicaciones , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Humanos , Enfermedades Pulmonares Intersticiales/etiología , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/radioterapia , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Estudios Retrospectivos
16.
Phys Rev Lett ; 105(6): 060401, 2010 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-20867961

RESUMEN

We propose a method of achieving large temperature T sensitivity in the Casimir force that involves measuring the stable separation between dielectric objects immersed in a fluid. We study the Casimir force between slabs and spheres using realistic material models, and find large >2 nm/K variations in their stable separations (hundreds of nanometers) near room temperature. In addition, we analyze the effects of Brownian motion on suspended objects, and show that the average separation is also sensitive to changes in T. Finally, this approach also leads to rich qualitative phenomena, such as irreversible transitions, from suspension to stiction, as T is varied.

17.
Phys Rev Lett ; 104(16): 160402, 2010 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-20482030

RESUMEN

We present a scheme for obtaining stable Casimir suspension of dielectric nontouching objects immersed in a fluid, validated here in various geometries consisting of ethanol-separated dielectric spheres and semi-infinite slabs. Stability is induced by the dispersion properties of real dielectric (monolithic) materials. A consequence of this effect is the possibility of stable configurations (clusters) of compact objects, which we illustrate via a molecular two-sphere dicluster geometry consisting of two bound spheres levitated above a gold slab. Our calculations also reveal a strong interplay between material and geometric dispersion, and this is exemplified by the qualitatively different stability behavior observed in planar versus spherical geometries.

18.
Nat Commun ; 11(1): 4422, 2020 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-32887875

RESUMEN

The ocean is a sink for ~25% of the atmospheric CO2 emitted by human activities, an amount in excess of 2 petagrams of carbon per year (PgC yr-1). Time-resolved estimates of global ocean-atmosphere CO2 flux provide an important constraint on the global carbon budget. However, previous estimates of this flux, derived from surface ocean CO2 concentrations, have not corrected the data for temperature gradients between the surface and sampling at a few meters depth, or for the effect of the cool ocean surface skin. Here we calculate a time history of ocean-atmosphere CO2 fluxes from 1992 to 2018, corrected for these effects. These increase the calculated net flux into the oceans by 0.8-0.9 PgC yr-1, at times doubling uncorrected values. We estimate uncertainties using multiple interpolation methods, finding convergent results for fluxes globally after 2000, or over the Northern Hemisphere throughout the period. Our corrections reconcile surface uptake with independent estimates of the increase in ocean CO2 inventory, and suggest most ocean models underestimate uptake.

19.
Opt Express ; 17(22): 19996-20011, 2009 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-19997224

RESUMEN

We analytically investigate the forces due to Surface Plasmon Polariton (SPP) modes between finite and infinitely thick metal slabs separated by an air gap. Using the Drude model and experimentally determined values of the dielectric functions of gold and silver, we study how frequency dispersion and loss in the metals affects the behavior of the SPP modes and the forces generated by them. We calculate the force using the Maxwell Stress Tensor for both the attractive and repulsive modes.


Asunto(s)
Oro/química , Oro/efectos de la radiación , Pinzas Ópticas , Plata/química , Plata/efectos de la radiación , Resonancia por Plasmón de Superficie/métodos , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo , Luz , Reproducibilidad de los Resultados , Dispersión de Radiación , Sensibilidad y Especificidad , Estrés Mecánico
20.
Br J Hosp Med (Lond) ; 80(4): 211-215, 2019 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-30951418

RESUMEN

This literature review clarifies the role of radiotherapy in the management of low-volume haemoptysis. Embase and Medline were interrogated, and PRISMA guidelines were then used to select relevant articles. Seventy-eight articles were considered relevant and manually reviewed. The evidence suggests that external beam radiotherapy is more effective than endobronchial brachytherapy at controlling low-volume haemoptysis. There is no evidence to recommend a combination of the two techniques. Different doses and fractionations appear equally effective, with a potential survival advantage of higher dose regimens for fitter patients. Palliative radiotherapy is effective at controlling low-volume haemoptysis. External beam radiotherapy is the first-line treatment, with endobronchial brachytherapy recommended following external beam radiotherapy failure. Choice of dose and fractionation should take into account the patient's performance status.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Hemoptisis/radioterapia , Hemorragia/radioterapia , Neoplasias Pulmonares/radioterapia , Carcinoma Pulmonar de Células Pequeñas/radioterapia , Braquiterapia , Broncoscopía , Carcinoma de Pulmón de Células no Pequeñas/complicaciones , Fraccionamiento de la Dosis de Radiación , Hemoptisis/etiología , Hemorragia/etiología , Humanos , Enfermedades Pulmonares/etiología , Enfermedades Pulmonares/radioterapia , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/secundario , Cuidados Paliativos , Carcinoma Pulmonar de Células Pequeñas/complicaciones
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